Pharmaceutical compositions comprising nitroxyl donors

ABSTRACT

The present disclosure provides nitroxyl donating pharmaceutical compositions comprising N-substituted hydroxylamine derivatives. The compositions are highly efficacious in treating cardiovascular diseases (e.g., heart failure), have a suitable toxicological profile, and are sufficiently stable for intravenous or oral administration.

1. BACKGROUND

Nitroxyl (HNO) has been shown to have positive cardiovascular effects inin vitro and in vivo models of failing hearts. However, at physiologicalpH, HNO dimerizes to hyponitrous acid, which subsequently dehydrates tonitrous oxide; due to this metastability, HNO for therapeutic use mustbe generated in situ from donor compounds. A variety of compoundscapable of donating nitroxyl have been described and proposed for use intreating disorders known or suspected to be responsive to nitroxyl. See,e.g., U.S. Pat. Nos. 6,936,639; 7,696,373; 8,030,356; 8,268,890;8,227,639; and 8,318,705 and U.S. pre-grant publication nos.2009/0281067; 2009/0298795; 2011/0136827; and 2011/0144067. Although allof these compounds are capable of donating nitroxyl, they differ invarious physicochemical properties, and there remains a need to identifynitroxyl donors that have physicochemical properties best suited fortreating specific clinical conditions via specific routes ofadministration.

U.S. Pat. No. 8,030,056 describes the synthesis of derivatives ofPiloty's acid type compounds that are capable of donating nitroxyl underphysiological conditions and are useful in treating heart failure andischemia/reperfusion injury. The nitroxyl donor CXL-1020(N-hydroxy-2-methanesulfonylbenzene-1-sulfonamide) has been evaluated ina Phase I safety study in healthy volunteers and in a Phase IIaplacebo-controlled, double-blind, dose-escalation study conducted atmultiple hospitals. Sabbah et al., “Nitroxyl (HNO) a novel approach forthe acute treatment of heart failure”, Circ Heart Fail., publishedonline Oct. 9, 2013 (Online ISSN: 1941-3297, Print ISSN: 1941-3289). Thestudies demonstrated that in patients with systolic heart failure,CXL-1020, when administered intravenously as an aqueous solution atpH=4, reduced both left and right heart filling pressures and systemicvascular resistance, while increasing cardiac and stroke volume index.Hence, the studies demonstrated that CXL-1020 enhances myocardialfunction in human patients suffering from heart failure. However, atthreshold doses of CXL-1020 needed to produce hemodynamic effects, thecompound was found to induce side effects, including unacceptable levelsof inflammatory irritation at and distal to the intravenous insertionsite, and the authors report that because of such side effects, thiscompound would not be a viable candidate for a human therapeutic.

Accordingly, there is a need to develop new nitroxyl donating compounds(referred to herein as nitroxyl donors) and compositions that are usefulfor the treatment of heart failure and that have a suitabletoxicological profile. Development of such compounds requires anunderstanding of the pharmacokinetic profile associated with nitroxyldonation and the factors influencing the toxicological profile. Failureto understand these factors has hampered the development of nitroxyldonors for clinical use.

Moreover, formulating nitroxyl donors has proven to be a considerablechallenge. Many of the current nitroxyl donors are insoluble in aqueoussolutions and/or are insufficiently stable. Solubility and stabilityproblems often preclude the use of such compounds in pharmaceuticalcompositions for parenteral and/or oral administration. Accordingly,there exists a need to develop compositions containing nitroxyl donorsat sufficient concentration for parenteral and/or oral administrationthat are sufficiently stable and have favorable pharmacological andtoxicological profiles.

Citation of any reference in Section 1 of this application is not to beconstrued as an admission that such reference is prior art to thepresent application.

2. SUMMARY OF THE DISCLOSURE

The present disclosure relates to the discovery of nitroxyl donatingcompositions that are highly effective in treating cardiovasculardiseases (e.g., heart failure), have a suitable toxicological profile,and are sufficiently stable for intravenous or oral administration.

It has been discovered that the toxicological profile ofN-hydroxysulfonamide type nitroxyl donors that have sufficiently longhalf-lives under physiological conditions is significantly better thanthe toxicological profile of N-hydroxysulfonamide type nitroxyl donorswith shorter half-lives (e.g., CXL-1020). In particular, it has beendiscovered that N-hydroxysulfonamide type nitroxyl donors with shorthalf-lives (i.e., 10 minutes or less when measured in an aeratedphosphate buffered saline (PBS) solution at a pH of 7.4 or in plasma(e.g., human plasma) according to the procedure described in Example 2(in Section 5.2) have undesirable toxicity when administeredparenterally (e.g., intravenously). It will be understood that the term“N-hydroxysulfonamide type nitroxyl donor” includes both compounds witha free sulfonamide hydroxyl group (e.g., compounds depicted in Tables 1and 2 of Section 4.2) and compounds in which the N-hydroxy group of thesulfonamide is esterified, as depicted below:

where

represents the aromatic, heteroaromatic or polycyclic portion of thecompound (see Section 4.2 for definitions of R).

In accordance with the present disclosure, N-hydroxysulfonamide typenitroxyl donors that have half-lives of greater than 10 minutes whenmeasured in PBS or human plasma show significant improvements in thetoxicological profile relative to N-hydroxysulfonamide type nitroxyldonors, such as CXL-1020, that have half-lives of less than 10 minutes,while retaining a high level of efficacy in the treatment ofcardiovascular diseases (e.g., heart failure).

In certain embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition (i.e., in a nitroxyl donatingcomposition) of the disclosure has a half-life of greater than 10minutes when measured in an aerated phosphate buffered saline (PBS)solution at a pH of 7.4 under conditions specified in Example 2. Inparticular embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure has a half-lifeof from about 12 minutes to about 150 minutes when measured in anaerated PBS solution at a pH of 7.4 under conditions specified inExample 2. In specific embodiments, a N-hydroxysulfonamide type nitroxyldonor useful in a pharmaceutical composition of the disclosure has ahalf-life of from about 15 minutes to about 70 minutes when measured inan aerated PBS solution at a pH of 7.4 under conditions specified inExample 2. Specific examples of such compounds of the disclosure arelisted in Tables 1 and 2 (see Section 4.2).

In certain embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure has a half-lifeof greater than 10 minutes when measured in human plasma at pH 7.4 inthe presence of an anticoagulant (e.g., heparin or sodium citrate),under conditions specified in Example 2. In particular embodiments, aN-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure has a half-life of from greater than 10minutes to about 85 minutes when measured in human plasma at a pH of 7.4under conditions specified in Example 2. In some embodiments, aN-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure has a half-life of from about 12 minutesto about 85 minutes when measured in human plasma at a pH of 7.4 underconditions specified in Example 2. In particular embodiments, aN-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure has a half-life of from about 25 minutesto about 75 minutes when measured in human plasma at a pH of 7.4 underconditions specified in Example 2. Specific examples of such compoundsof the disclosure are listed in Tables 1 and 2.

In a particular embodiment, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is a compoundof the formula (1):

In another embodiment, a N-hydroxysulfonamide type nitroxyl donor usefulin a pharmaceutical composition of the disclosure is a compound of theformula (2):

It has further been discovered that a composition comprising aN-hydroxysulfonamide type nitroxyl donor formulated at a pH of about 5or greater has a significantly improved toxicological profile relativeto compositions comprising the N-hydroxysulfonamide type nitroxyl donorformulated at more acidic pH levels, such as the CXL-1020 compositionsevaluated in Phase I and Phase IIa clinical trials. Thus, in variousembodiments, a N-hydroxysulfonamide type nitroxyl donor can beformulated for parenteral injection at a pH of from about 5 to about 6(e.g., a pH of about 5, about 5.5 or about 6). Formulating within thispH range mitigates potential undesirable side effects (e.g., reducedvenous irritation) relative to more acidic compositions. Surprisingly,formulating a N-hydroxysulfonamide type nitroxyl donor at a pH withinthe range of a pH of from about 5 to about 6 can be achieved without adeleterious effect on the stability of the nitroxyl donors.

Additionally, it has been discovered that particular excipients can beused to stabilize and/or solubilize nitroxyl donors useful incompositions of the disclosure. In various embodiments, at least onesuch pharmaceutically acceptable excipient comprises at least onespecies of cyclodextrin. In one such embodiment, the excipient is aβ-cyclodextrin. One preferred β-cyclodextrin is CAPTISOL®.

In embodiments where a cyclodextrin (e.g., CAPTISOL®) serves anexcipient in the disclosed pharmaceutical compositions, the quantity ofthe cyclodextrin in the composition will depend on the solubility and/orstability of the nitroxyl donor. For example, the molar ratio betweenthe N-hydroxysulfonamide type nitroxyl donor and the cyclodextrinpresent in the composition can be from about 0.02:1 to about 2:1. Inparticular embodiments, the molar ratio between the N-hydroxysulfonamidetype nitroxyl donor and the cyclodextrin present in the composition canbe from about 0.05:1 to about 1.5:1. In certain embodiments, the molarratio between the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition can be from about 0.1:1 to about1:1. In certain embodiments, the molar ratio between theN-hydroxysulfonamide type nitroxyl donor and the cyclodextrin present inthe composition can be from about 0.5:1 to about 1:1.

Compounds and/or compositions of the disclosure can be used to treat avariety of conditions that are responsive to nitroxyl therapy. Forinstance, the compounds and/or compositions of the disclosure can beused to treat or prevent the occurrence of cardiovascular diseases. Incertain embodiments, a nitroxyl donating composition of the disclosurecan be used to treat cardiovascular disease, ischemia/reperfusioninjury, pulmonary hypertension or another condition responsive tonitroxyl therapy. In particular embodiments, a nitroxyl donatingcomposition of the disclosure can be used to treat heart failure. In aparticular embodiment, a compound and/or composition of the disclosurecan be used to treat decompensated heart failure (e.g., acutedecompensated heart failure). In certain embodiments, the compoundsand/or compositions of the disclosure can be used to treat systolicheart failure. In particular embodiments, the compounds and/orcompositions of the disclosure can be used to treat diastolic heartfailure.

In one aspect, the compound and/or composition of the disclosure can beadministered via parenteral (e.g., subcutaneous, intramuscular,intravenous or intradermal) administration. When administeredparenterally (e.g., intravenously) to a human subject, aN-hydroxysulfonamide type nitroxyl donor useful in, for example, apharmaceutical composition of the disclosure, can be dosed at a rate offrom about 5 μg/kg/min to about 100 μg/kg/min. In certain embodiments, aN-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure can be dosed to a human subject at a rateof from about 10 μg/kg/min to about 70 μg/kg/min. In certainembodiments, a N-hydroxysulfonamide type nitroxyl donor useful in apharmaceutical composition of the disclosure can be dosed to a humansubject at a rate of from about 15 μg/kg/min to about 50 μg/kg/min. Incertain embodiments, a N-hydroxysulfonamide type nitroxyl donor usefulin a pharmaceutical composition of the disclosure can be dosed to ahuman subject at a rate of from about 20 μg/kg/min to about 30μg/kg/min. In certain embodiments, a N-hydroxysulfonamide type nitroxyldonor useful in a pharmaceutical composition of the disclosure can bedosed to a human subject at a rate of from about 10 μg/kg/min to about20 μg/kg/min.

In another embodiment, the compounds and/or compositions of thedisclosure can be formulated for oral administration. Compounds for oraladministration can be formulated as liquid or solid dosage forms. Inparticular embodiments where a nitroxyl donor is formulated as an oralliquid dosage form, polyethylene glycol 300 (PEG300) can serve as anexemplary excipient.

3. BRIEF DESCRIPTION OF FIGURES

FIG. 1 shows the hemodynamic profile of CXL-1020 and five compoundsuseful in pharmaceutical compositions of the disclosure (compounds offormulas (1), (2), (83), (84) and (85)) using a caninetachycardia-pacing model of heart failure (see Example 3). Each compoundwas administered intravenously at a rate of 100 μg/kg/min. Hemodynamicparameters were obtained 180 minutes after administration of therespective compound.

FIG. 2 shows the assessment of the toxicological profile of CXL-1020 andcompounds useful in pharmaceutical compositions of the disclosure(compounds of formulas (1), (2), (83), (84), (85) and (86)) following 24hour infusion at multiple doses using a canine peripheral vein toxicitymodel (see Example 5). Key inflammatory markers measured include whiteblood cells (WBC), fibrinogen, and C-reactive protein (CRP).

FIG. 3 shows measures of inflammation observed using a canine implantedcentral catheter 72 hour model using different doses of CXL-1020 andfour compounds useful in pharmaceutical compositions of the disclosure(compounds of formulas (1), (2), (83) and (84)) (see Example 5). Scoresshown in the table are based on microscopic pathology findings of edema,hemorrhage, vascular inflammation and perivascular inflammation observedat and around the catheter tip and proximal to the catheter tip.

FIG. 4 shows the assessment of the toxicological profile of CXL-1020 andtwo compounds of the disclosure (compounds of formulas (2) and (86)),formulated at a pH of 4 or 6, following 24 hour infusion at a rate of 3μg/kg/min (see Examples 4 and 6).

4. DETAILED DESCRIPTION

The invention includes the following:

(1.) A method of treating heart failure, comprising administering to ahuman patient a nitroxyl donor composition, said composition comprisinga N-hydroxysulfonamide type nitroxyl donor that has a half-life ofgreater than 10 minutes when measured in human plasma at a pH of 7.4 bythe procedure described in Example 2 and a cyclodextrin.

(2.) The method of the above (1.), wherein the N-hydroxysulfonamide typenitroxyl donor has a half-life of from about 12 minutes to about 85minutes when measured in human plasma at a pH of 7.4 under conditionsspecified in Example 2.

(3.) The method of the above (1.), wherein the N-hydroxysulfonamide typenitroxyl donor has a half-life of from about 25 minutes to about 75minutes when measured in human plasma at a pH of 7.4 under conditionsspecified in Example 2.

(4.) The method of the above (1.), wherein the N-hydroxysulfonamide typenitroxyl donor has a half-life of less than 95 minutes when measured inhuman plasma at a pH of 7.4 under conditions specified in Example 2.

(5.) The method of any one of the above (1.)-(4.), wherein thecyclodextrin is a sulfo-n-butyl ether derivative of β-cyclodextrinhaving six or seven sulfo-n-butyl ether groups per cyclodextrinmolecule.

(6.) The method of any one of the above (1.)-(4.), wherein thecyclodextrin is CAPTISOL®.

(7.) The method of any one of the above (1.)-(6.), wherein the molarratio between the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition is from about 0.02:1 to about2:1.

(8.) The method of any one of the above (1.)-(6.), wherein the molarratio between the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition is from about 0.05:1 to about1.5:1.

(9.) The method of any one of the above (1.)-(6.), wherein the molarratio between the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition is from about 0.5:1 to about1:1.

(10.) The method of any one of the above (1.)-(9.), wherein thecomposition is suitable for parenteral administration.

(11.) The method of the above (10.), wherein the composition is suitablefor intravenous administration.

(12.) The method of the above (10.) or the above (11.), wherein thecomposition is formulated at a pH of from about 4 to about 6.

(13.) The method of the above (10.) or the above (11.), wherein thecomposition is formulated at a pH of from about 5 to about 6.

(14.) The method of the above (10.) or the above (11.), wherein thecomposition is formulated at a pH of from about 5.5 to about 6.

(15.) The method of any one of the above (1.)-(14.), wherein the heartfailure is acute decompensated heart failure.

(16.) The method of any one of the above (1.)-(15.), wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(1):

(17.) The method of any one of the above (1.)-(15.), wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(2):

(18.) A method of treating heart failure, comprising administering to ahuman patient a nitroxyl donor composition comprising aN-hydroxysulfonamide type nitroxyl donor that has a half-life of greaterthan 10 minutes when measured in human plasma at a pH of 7.4 by theprocedure described in Example 2, wherein said composition isadministered parenterally at a pH of from about 5 to about 6.5.

(19.) The method of the above (18.), wherein the composition isadministered intravenously.

(20.) The method of the above (18.) or the above (19.), wherein thecomposition is administered at a pH of from about 5.5 to about 6.

(21.) The method of the above (18.) or the above (19.), wherein thecomposition is administered at a pH of about 6.

(22.) The method of any one of the above (18.)-(21.), wherein theN-hydroxysulfonamide type nitroxyl donor has a half-life of from about12 minutes to about 85 minutes when measured in human plasma at a pH of7.4 under conditions specified in Example 2.

(23.) The method of any one of the above (18.)-(21.), wherein theN-hydroxysulfonamide type nitroxyl donor has a half-life of from about25 minutes to about 75 minutes when measured in human plasma at a pH of7.4 under conditions specified in Example 2.

(24.) The method of any one of the above (18.)-(21.), wherein theN-hydroxysulfonamide type nitroxyl donor has a half-life of less than 95minutes when measured in human plasma at a pH of 7.4 under conditionsspecified in Example 2.

(25.) The method of any one of the above (18.)-(24.), wherein thecomposition further comprises a stabilizing agent.

(26.) The method of the above (25.), wherein the stabilizing agent is acyclodextrin.

(27.) The method of the above (26.), wherein the cyclodextrin is aβ-cyclodextrin.

(28.) The method of any one of the above (18.)-(27.), wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(1):

(29.) The method of any one of the above (18.)-(27.), wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(2):

(30.) A pharmaceutical composition comprising a N-hydroxysulfonamidetype nitroxyl donor that has a half-life of greater than 10 minutes whenmeasured in human plasma at a pH of 7.4 by the procedure described inExample 2 and an aqueous buffer, wherein the composition has a pH offrom about 5 to about 6.

(31.) The pharmaceutical composition of the above (30.), wherein theaqueous buffer provides a pH to the composition of from about 5.5 toabout 6.2.

(32.) The pharmaceutical composition of the above (30.), wherein theaqueous buffer provides a pH to the composition of about 6.

(33.) The pharmaceutical composition of any one of the above(30.)-(32.), wherein the buffer is a phosphate or acetate buffer.

(34.) The pharmaceutical composition of the above (33.), wherein thebuffer is a potassium phosphate buffer.

(35.) The pharmaceutical composition of the above (33.), wherein thebuffer is a potassium acetate buffer.

(36.) The pharmaceutical composition of any one of the above(30.)-(35.), further comprising a stabilizing agent.

(37.) The pharmaceutical composition of the above (36.), wherein thestabilizing agent is a cyclodextrin.

(38.) The pharmaceutical composition of the above (37.), wherein thecyclodextrin is a sulfo-n-butyl ether derivative of β-cyclodextrinhaving six or seven sulfo-n-butyl ether groups per cyclodextrinmolecule.

(39.) The pharmaceutical composition of the above (37.) or the above(38.), wherein the cyclodextrin is CAPTISOL®.

(40.) The pharmaceutical composition of any one of the above(37.)-(39.), wherein the molar ratio between the N-hydroxysulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.02:1 to about 2:1.

(41.) The pharmaceutical composition of any one of the above(37.)-(39.), wherein the molar ratio between the N-hydroxysulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.05:1 to about 1.5:1.

(42.) The pharmaceutical composition of any one of the above(37.)-(39.), wherein the molar ratio between the N-hydroxysulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.5:1 to about 1:1.

(43.) The pharmaceutical composition of any one of the above(30.)-(42.), wherein the N-hydroxysulfonamide type nitroxyl donor has ahalf-life of from about 12 minutes to about 85 minutes when measured inhuman plasma at a pH of 7.4 under conditions specified in Example 2.

(44.) The pharmaceutical composition of any one of the above(30.)-(42.), wherein the N-hydroxysulfonamide type nitroxyl donor has ahalf-life of from about 25 minutes to about 75 minutes when measured inhuman plasma at a pH of 7.4 under conditions specified in Example 2.

(45.) The pharmaceutical composition of any one of the above(30.)-(42.), wherein the N-hydroxysulfonamide type nitroxyl donor has ahalf-life of less than 95 minutes when measured in human plasma at a pHof 7.4 under conditions specified in Example 2.

(46.) The pharmaceutical composition of any one of the above(30.)-(42.), wherein the N-hydroxysulfonamide type nitroxyl donor is acompound of the formula (1)

(47.) The pharmaceutical composition of any one of the above(30.)-(42.), wherein the N-hydroxysulfonamide type nitroxyl donor is acompound of the formula (2):

(48.) A pharmaceutical composition comprising (i) a N-hydroxysulfonamidetype nitroxyl donor that has a half-life of greater than 10 minutes whenmeasured in human plasma at a pH of 7.4 by the procedure described inExample 2 and (ii) a cyclodextrin.

(49.) The pharmaceutical composition of the above (48.), wherein theN-hydroxysulfonamide type nitroxyl donor has a half-life of from about12 minutes to about 85 minutes when measured in human plasma at a pH of7.4 under conditions specified in Example 2.

(50.) The pharmaceutical composition of the above (48.), wherein theN-hydroxysulfonamide type nitroxyl donor has a half-life of from about25 minutes to about 75 minutes when measured in human plasma at a pH of7.4 under conditions specified in Example 2.

(51.) The pharmaceutical composition of the above (48.), wherein theN-hydroxysulfonamide type nitroxyl donor has a half-life of less than 95minutes when measured in human plasma at a pH of 7.4 under conditionsspecified in Example 2.

(52.) The pharmaceutical composition of any one of the above(48.)-(51.), wherein the cyclodextrin is a sulfo-n-butyl etherderivative of β-cyclodextrin having six or seven sulfo-n-butyl ethergroups per cyclodextrin molecule.

(53.) The pharmaceutical composition of any one of the above(48.)-(51.), wherein the cyclodextrin is CAPTISOL®.

(54.) The pharmaceutical composition of any one of the above(48.)-(53.), wherein the molar ratio between the N-hydroxysulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.02:1 to about 2:1.

(55.) The pharmaceutical composition of any one of the above(48.)-(53.), wherein the molar ratio between the N-hydroxy sulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.05:1 to about 1.5:1.

(56.) The pharmaceutical composition of any one of the above(48.)-(53.), wherein the molar ratio between the N-hydroxy sulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.5:1 to about 1:1.

(57.) The pharmaceutical composition of any one of the above(48.)-(53.), wherein the N-hydroxysulfonamide type nitroxyl donor is acompound of the formula (1):

(58.) The pharmaceutical composition of any one of the above(48.)-(53.), wherein the N-hydroxysulfonamide type nitroxyl donor is acompound of the formula (2):

(59.) An admixture comprising a N-hydroxysulfonamide type nitroxyl donorthat has a half-life of greater than 10 minutes when measured in humanplasma at a pH of 7.4 by the procedure described in Example 2 and acyclodextrin, wherein the molar ratio between the N-hydroxysulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.02:1 to about 2:1.

(60.) The admixture of the above (59.), which is formed bylyophilization.

(61.) The admixture of the above (59.) or the above (60.), wherein themolar ratio between the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition is from about 0.05:1 to about1.5:1.

(62.) The admixture of the above (61.), wherein the molar ratio betweenthe N-hydroxysulfonamide type nitroxyl donor and the cyclodextrinpresent in the composition is from about 0.5:1 to about 1:1.

(63.) The admixture of any one of the above (59.)-(62.), furthercomprising a buffering agent.

(64.) The admixture of the above (63.), wherein the buffering agent ispotassium acetate.

(65.) The admixture of any one of the above (59.)-(64.), wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(1):

(66.) The admixture of any one of the above (59.)-(64.), wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(2):

(67.) Use of a pharmaceutical composition of any one of the above(30.)-(58.) for the manufacture of a medicament useful for treating acardiovascular disease.

(68.) Use of a pharmaceutical composition of any one of the above(30.)-(58.) for the manufacture of a medicament useful for treatingheart failure.

(69.) Use of a pharmaceutical composition of any one of the above(30.)-(58.) for the manufacture of a medicament useful for treatingacute decompensated heart failure.

(70.) The pharmaceutical composition of any one of the above (30.)-(58.)for use in the treatment of a cardiovascular disease.

(71.) The pharmaceutical composition of any one of the above (30.)-(58.)for use in the treatment of heart failure.

(72.) The pharmaceutical composition of any one of the above (30.)-(58.)for use in the treatment of acute decompensated heart failure.

4.1 Definitions

Unless clearly indicated otherwise, the following terms as used hereinhave the meanings indicated below.

A “pharmaceutically acceptable salt” refers to a salt of any therapeuticagent disclosed herein, which salt can include any of a variety oforganic and inorganic counter ions known in the art and which salt ispharmaceutically acceptable. When the therapeutic agent contains anacidic functionality, various exemplary embodiments of counter ions aresodium, potassium, calcium, magnesium, ammonium, tetraalkylammonium, andthe like. When the therapeutic agent contains a basic functionality, apharmaceutically acceptable salt can include as a counter ion, by way ofexample, an organic or inorganic acid, such as hydrochloride,hydrobromide, tartrate, mesylate, acetate, maleate, oxalate, and thelike. Illustrative salts include, but are not limited to, sulfate,citrate, acetate, chloride, bromide, iodide, nitrate, bisulfate,phosphate, acid phosphate, lactate, salicylate, acid citrate, tartrate,oleate, tannate, pantothenate, bitartrate, ascorbate, succinate,maleate, besylate, fumarate, gluconate, glucaronate, saccharate,formate, benzoate, glutamate, methanesulfonate, ethanesulfonate,benzenesulfonate, and p-toluenesulfonate salts. Accordingly, a salt canbe prepared from a compound of any one of the formulae disclosed hereinhaving an acidic functional group, such as a carboxylic acid functionalgroup, and a pharmaceutically acceptable inorganic or organic base.Suitable bases include, but are not limited to, hydroxides of alkalimetals such as sodium, potassium, and lithium; hydroxides of alkalineearth metal such as calcium and magnesium; hydroxides of other metals,such as aluminum and zinc; ammonia, and organic amines, such asunsubstituted or hydroxy-substituted mono-, di-, or trialkylamines;dicyclohexylamine; tributyl amine; pyridine; N-methyl-N-ethylamine;diethylamine; triethylamine; mono-, bis-, or tris-(2-hydroxy-lower-alkylamines), such as mono-, bis-, or tris-(2-hydroxyethyl)amine,2-hydroxy-tert-butylamine, or tris-(hydroxymethyl)methylamine,N,N-di-lower-alkyl-N-(hydroxy-lower-alkyl)-amines, such asN,N-dimethyl-N-(2-hydroxyethyl) amine, or tri-(2-hydroxyethyl)amine;N-methyl-D-glucamine; and amino acids such as arginine, lysine, and thelike. A salt can also be prepared from a compound of any one of theformulae disclosed herein having a basic functional group, such as anamino functional group, and a pharmaceutically acceptable inorganic ororganic acid. Suitable acids include hydrogen sulfate, citric acid,acetic acid, hydrochloric acid (HCl), hydrogen bromide (HBr), hydrogeniodide (HI), nitric acid, phosphoric acid, lactic acid, salicylic acid,tartaric acid, ascorbic acid, succinic acid, maleic acid, besylic acid,fumaric acid, gluconic acid, glucaronic acid, formic acid, benzoic acid,glutamic acid, methanesulfonic acid, ethanesulfonic acid,benzenesulfonic acid, and p-toluenesulfonic acid.

“Pharmaceutically acceptable excipient” refers to any substance, notitself a therapeutic agent, used as a carrier, diluent, adjuvant,binder, and/or vehicle for delivery of a therapeutic agent to a patient,or added to a pharmaceutical composition to improve its handling orstorage properties or to permit or facilitate formation of a compound orpharmaceutical composition into a unit dosage form for administration.Pharmaceutically acceptable excipients are known in the pharmaceuticalarts and are disclosed, for example, in Gennaro, Ed., Remington: TheScience and Practice of Pharmacy, 20^(th) Ed. (Lippincott Williams &Wilkins, Baltimore, Md., 2000) and Handbook of PharmaceuticalExcipients, American Pharmaceutical Association, Washington, D.C.,(e.g., 1^(st), 2^(nd) and 3^(rd) Eds. a 1986, 1994 and 2000,respectively). As will be known to those in the art, pharmaceuticallyacceptable excipients can provide a variety of functions and can bedescribed as wetting agents, buffering agents, suspending agents,lubricating agents, emulsifiers, disintegrants, absorbents,preservatives, surfactants, colorants, flavorants, and sweeteners.Examples of pharmaceutically acceptable excipients include withoutlimitation: (1) sugars, such as lactose, glucose and sucrose; (2)starches, such as corn starch and potato starch; (3) cellulose and itsderivatives, such as sodium carboxymethyl cellulose, ethyl cellulose,cellulose acetate, hydroxypropylmethylcellulose, andhydroxypropylcellulose; (4) powdered tragacanth; (5) malt; (6) gelatin;(7) talc; (8) excipients, such as cocoa butter and suppository waxes;(9) oils, such as peanut oil, cottonseed oil, safflower oil, sesame oil,olive oil, corn oil and soybean oil; (10) glycols, such as propyleneglycol; (11) polyols, such as glycerin, sorbitol, mannitol andpolyethylene glycol; (12) esters, such as ethyl oleate and ethyllaurate; (13) agar; (14) buffering agents, such as magnesium hydroxideand aluminum hydroxide; (15) alginic acid; (16) pyrogen-free water; (17)isotonic saline; (18) Ringer's solution; (19) ethyl alcohol; (20) pHbuffered solutions; (21) polyesters, polycarbonates and/orpolyanhydrides; and (22) other non-toxic compatible substances employedin pharmaceutical formulations.

“Unit dosage form” refers to a physically discrete unit suitable as aunitary dosage for a human or an animal. Each unit dosage form cancontain a predetermined amount of a therapeutic agent calculated toproduce a desired effect.

Unless clearly indicated otherwise, a “patient” refers to an animal,such as a mammal, including but not limited to, a human. Hence, themethods disclosed herein can be useful in human therapy and veterinaryapplications. In particular embodiments, the patient is a mammal. Incertain embodiments, the patient is a human.

“Effective amount” refers to such amount of a therapeutic agent or apharmaceutically acceptable salt thereof, which in combination with itsparameters of efficacy and potential for toxicity, as well as based onthe knowledge of the practicing specialist, should be effective in agiven therapeutic form. As is understood in the art, an effective amountcan be administered in one or more doses.

“Treatment”, “treating” and the like is an approach for obtaining abeneficial or desired result, including clinical results. For purposesof this disclosure, beneficial or desired results include but are notlimited to inhibiting and/or suppressing the onset and/or development ofa condition or reducing the severity of such condition, such as reducingthe number and/or severity of symptoms associated with the condition,increasing the quality of life of those suffering from the condition,decreasing the dose of other medications required to treat thecondition, enhancing the effect of another medication a patient istaking for the condition, and/or prolonging survival of patients havingthe condition.

“Prevent”, “preventing” and the like refers to reducing the probabilityof developing a condition in a patient who does not have, but is at riskof developing a condition. A patient “at risk” may or may not have adetectable condition, and may or may not have displayed a detectablecondition prior to the treatment methods disclosed herein. “At risk”denotes that a patient has one or more so-called risk factors, which aremeasurable parameters that correlate with development of a condition andare known in the art. A patient having one or more of these risk factorshas a higher probability of developing the condition than a patientwithout such risk factor(s).

“Positive inotrope” refers to an agent that causes an increase inmyocardial contractile function. Exemplary positive inotropes are abeta-adrenergic receptor agonist, an inhibitor of phosphodiesteraseactivity, and calcium-sensitizers. Beta-adrenergic receptor agonistsinclude, among others, dopamine, dobutamine, terbutaline, andisoproterenol. Analogs and derivatives of such compounds are alsointended. For example, U.S. Pat. No. 4,663,351 discloses a dobutamineprodrug that can be administered orally.

A condition that is “responsive to nitroxyl therapy” includes anycondition in which administration of a compound that donates aneffective amount of nitroxyl under physiological conditions treatsand/or prevents the condition, as those terms are defined herein. Acondition whose symptoms are suppressed or diminished uponadministration of nitroxyl donor is a condition responsive to nitroxyltherapy.

“Pulmonary hypertension” or “PH” refers to a condition in which thepulmonary arterial pressure is elevated. The current hemodynamicdefinition of PH is a mean pulmonary arterial pressure (MPAP) at rest ofgreater than or equal to 25 mmHg. Badesch et al., J. Amer. Coll.Cardiol. 54(Suppl.):S55-S66 (2009).

“N/A” means not assessed.

“(C₁-C₆)alkyl” refers to saturated linear and branched hydrocarbonstructures having 1, 2, 3, 4, 5, or 6 carbon atoms. When an alkylresidue having a specific number of carbons is named, all geometricisomers having that number of carbons are intended to be encompassed;thus, for example, “propyl” includes n-propyl and iso-propyl and “butyl”includes n-butyl, sec-butyl, iso-butyl and tert-butyl. Examples of(C₁-C₆)alkyl groups include methyl, ethyl, n-propyl, iso-propyl,n-butyl, tert-butyl, n-hexyl, and the like.

“(C₁-C₄)alkyl” refers to saturated linear and branched hydrocarbonstructures having 1, 2, 3, or 4 carbon atoms. Examples of (C₁-C₄)alkylgroups include methyl, ethyl, n-propyl, iso-propyl, n-butyl andtert-butyl.

“(C₃-C₅)alkyl” refers to saturated linear and branched hydrocarbonstructures having 3, 4, or 5 carbon atoms. When an alkyl residue havinga specific number of carbons is named, all geometric isomers having thatnumber of carbons are intended to be encompassed; thus, for example,“propyl” includes n-propyl and iso-propyl and “butyl” includes n-butyl,sec-butyl, iso-butyl and tert-butyl. Examples of (C₃-C₅)alkyl groupsinclude n-propyl, iso-propyl, n-butyl, tert-butyl, n-pentyl, and thelike.

“(C₂-C₄)alkenyl” refers to a straight-chain or branched unsaturatedhydrocarbon radical having 2, 3, or 4 carbon atoms and a double bond inany position, e.g., ethenyl, 1-propenyl, 2-propenyl (allyl), 1-butenyl,2-butenyl, 3-butenyl, 1-methylethenyl, 1-methyl-1-propenyl,2-methyl-2-propenyl, 2-methyl-1-propenyl, 1-methyl-2-propenyl, and thelike.

“(C₂-C₃)alkynyl” refers to a straight chain non-cyclic hydrocarbonhaving 2 or 3 carbon atoms and including at least one carbon-carbondouble bond. Examples of (C₂-C₃)alkenyls include -vinyl, -allyl, and1-prop-1-enyl.

“(C₅-C₇)heterocycloalkyl” refers to a 5-, 6-, or 7-membered, saturatedor unsaturated, bridged, mono- or bicyclic-heterocycle containing 1, 2,3, or 4 ring heteroatoms each independently selected from nitrogen,oxygen, and sulfur. Examples of (C₅-C₇)heterocycloalkyl groups includepyrazolyl, pyrrolidinyl, piperidinyl, piperazinyl, tetrahydro-oxazinyl,tetrahydrofuran, thiolane, dithiolane, pyrroline, pyrrolidine,pyrazoline, pyrazolidine, imidazoline, imidazolidine, tetrazole,piperidine, pyridazine, pyrimidine, pyrazine, tetrahydrofuranone,γ-butyrolactone, α-pyran, γ-pyran, dioxolane, tetrahydropyran, dioxane,dihydrothiophene, piperazine, triazine, tetrazine, morpholine,thiomorpholine, diazepan, oxazine, tetrahydro-oxazinyl, isothiazole,pyrazolidine, and the like.

“(5- or 6-membered)heteroaryl” refers to a monocyclic aromaticheterocycle ring of 5 or 6 members, i.e., a monocyclic aromatic ringcomprising at least one ring heteroatom, e.g., 1, 2, 3, or 4 ringheteroatoms, each independently selected from nitrogen, oxygen, andsulfur. Examples of -(5- or 6-membered)heteroaryls include pyridyl,pyrrolyl, furyl, imidazolyl, oxazolyl, imidazolyl, thiazolyl,isoxazolyl, 1,2,3-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl,1,2,3-triazolyl, pyrazolyl, isothiazolyl, pyridazinyl, pyrimidyl,pyrazinyl, 1,2,3-thiadiazolyl, 1,3,4-thiadiazolyl, 1,2,5-thiadiazolyl,1,3,5-triazinyl, and thiophenyl.

“Halo” refers to —F, —Cl, —Br or —I.

“Sulfo-n-butyl ether derivative of β-cyclodextrin” refers toβ-cyclodextrin having at least one —OH group that is derivatized byreplacing the hydrogen atom thereof with —(CH₂)₄—S(O)₂—OH or—(CH₂)₄—S(O)₂—O⁻Z⁺ to provide a —O—(CH₂)₄—S(O)₂—OH or—O—(CH₂)₄—S(O)₂—O⁻Z⁺ group, respectively, where Z⁺ is a cation such assodium, potassium, ammonium, tetramethylammonium, and the like. In oneembodiment, each Z is sodium.

4.2 N-Hydroxysulfonamide Type Nitroxyl Donors

It has been discovered that N-hydroxysulfonamide type nitroxyl donorsthat have sufficiently long half-lives under physiological conditionshave significantly better toxicological profiles as compared toN-hydroxysulfonamide type nitroxyl donors that have shorter half-lives(e.g., CXL-1020). These longer half-life nitroxyl donors provideefficacy levels similar to CXL-1020 when administered intravenously butshow significantly reduced side effects (e.g., irritation and/orinflammation) (see Examples 4-6). Moreover, these nitroxyl donorsprovide an onset of hemodynamic effects in 1 hour or less, which isclinically desirable.

Without being bound by theory, the experiments reported in the Examplesof this disclosure suggest that nitroxyl donors with half-livessubstantially shorter than 10 minutes when measured in PBS or humanplasma (see Example 2), such as CXL-1020, produce high localconcentrations of nitroxyl upon administration, and that the high localconcentration of nitroxyl is a cause of the observed side effects.Nitroxyl at high concentration dimerizes, resulting in the formation ofhyponitrous acid, which is capable of producing hydroxyl radicals.Alternatively, or in addition, peroxide emanating from white blood cellscan react with nitroxyl to form hydroxyl radicals. Hydroxyl radicals canbe toxic to endothelial cells, resulting in inflammation or intolerance.While nitroxyl compounds with longer half-lives could, in theory,produce hydroxyl radicals through similar mechanisms, formation of suchradicals would be expected to be reduced by virtue of the lowconcentrations of nitroxyl, thus reducing the ability of nitroxyl todimerize or react with peroxide. Compounds with very long half-lives(e.g., greater than 95 minutes when measured in human plasma inaccordance with the method described in Example 2) would therefore beexpected to have a favorable toxicological profile; however, becausethese compounds would be expected to be cleared from the circulationand/or diluted prior to substantial nitroxyl formation, such compoundsare expected to have low efficacy.

Accordingly, the disclosure provides pharmaceutical compositionscomprising N-hydroxysulfonamide type nitroxyl donors with half-livesgreater than about 10 minutes when measured in an aerated phosphatebuffered saline (PBS) solution at pH 7.4, or in human plasma in thepresence of an anticoagulant (e.g., heparin or sodium citrate) at pH7.4, each in accordance with the procedure described in Example 2. Inparticular embodiments, the disclosure provides pharmaceuticalcompositions comprising N-hydroxysulfonamide type nitroxyl donors withhalf-lives greater than about 17 minutes when measured in an aeratedphosphate buffered saline (PBS) solution at pH 7.4, or in human plasmain the presence of an anticoagulant (e.g., heparin or sodium citrate) atpH 7.4, each in accordance with the procedure described in Example 2.

N-hydroxysulfonamide type nitroxyl donors with half-lives within therange of from about 12 minutes to about 85 minutes when measured in anaerated phosphate buffered saline (PBS) solution at pH 7.4, or in humanplasma in the presence of an anticoagulant (e.g., heparin or sodiumcitrate) at pH 7.4, each in accordance with the procedure described inExample 2, have been found to have favorable efficacy and an improvedtoxicological profile relative to compounds with shorter half-lives. Incertain embodiments, a N-hydroxysulfonamide type nitroxyl donor usefulin a pharmaceutical composition of the disclosure has a half-life offrom about 15 minutes to about 80 minutes when measured in an aeratedphosphate buffered saline (PBS) solution at pH 7.4, or in human plasmain the presence of an anticoagulant (e.g., heparin or sodium citrate) atpH 7.4, each in accordance with the procedure described in Example 2. Inparticular embodiments, a nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure has a half-life of from about 25 minutesto about 75 minutes when measured in an aerated phosphate bufferedsaline (PBS) solution at pH 7.4, or in human plasma in the presence ofan anticoagulant (e.g., heparin or sodium citrate) at pH 7.4, each inaccordance with the procedure described in Example 2. In particularembodiments, a nitroxyl donor useful in a pharmaceutical composition ofthe disclosure has a half-life of from about 25 minutes to about 60minutes when measured in an aerated phosphate buffered saline (PBS)solution at pH 7.4, or in human plasma in the presence of ananticoagulant (e.g., heparin or sodium citrate) at pH 7.4, each inaccordance with the procedure described in Example 2. In particularembodiments, a nitroxyl donor useful in a pharmaceutical composition ofthe disclosure has a half-life of from about 35 minutes to about 60minutes when measured in an aerated phosphate buffered saline (PBS)solution at pH 7.4, or in human plasma in the presence of ananticoagulant (e.g., heparin or sodium citrate) at pH 7.4, each inaccordance with the procedure described in Example 2. In particularembodiments, a nitroxyl donor useful in a pharmaceutical composition ofthe disclosure has a half-life of from about 35 minutes to about 50minutes when measured in an aerated phosphate buffered saline (PBS)solution at pH 7.4, or in human plasma in the presence of ananticoagulant (e.g., heparin or sodium citrate) at pH 7.4, each inaccordance with the procedure described in Example 2. In particularembodiments, a nitroxyl donor useful in a pharmaceutical composition ofthe disclosure has a half-life of from about 40 minutes to about 50minutes an aerated phosphate buffered saline (PBS) solution at pH 7.4,or in human plasma in the presence of an anticoagulant (e.g., heparin orsodium citrate) at pH 7.4, each in accordance with the proceduredescribed in Example 2.

N-hydroxysulfonamide type nitroxyl donors useful in pharmaceuticalcompositions of the disclosure are capable of donating nitroxyl atphysiological pH (i.e., a pH of about 7.4) and physiological temperature(i.e., a temperature of about 37° C.) (together, “physiologicalconditions”). The level of nitroxyl donating ability can be expressed asa percentage of a N-hydroxysulfonamide type nitroxyl donor's theoreticalstoichiometric maximum. A compound that donates a “significant level ofnitroxyl” means, in various embodiments, a N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition of the disclosurethat donates about 40% or more, about 50% or more, about 60% or more,about 70% or more, about 80% or more, about 90% or more, or about 95% ormore of its theoretical maximum amount of nitroxyl under physiologicalconditions. In particular embodiments, a N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition donates from about70% to about 90% of its theoretical maximum amount of nitroxyl. Inparticular embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure donates fromabout 85% to about 95% of its theoretical maximum amount of nitroxyl. Inparticular embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition donates from about 90% to about95% of its theoretical maximum amount of nitroxyl. Compounds that donateless than about 40%, or less than about 50%, of their theoreticalmaximum amount of nitroxyl are still nitroxyl donors and can be used inthe methods disclosed. A N-hydroxysulfonamide type nitroxyl donor thatdonates less than about 50% of its theoretical amount of nitroxyl can beused in the methods disclosed, but may require higher dosing levels ascompared to a N-hydroxy sulfonamide type nitroxyl donor that donates ahigher level of nitroxyl.

It will be understood that a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure can also donatea limited amount of nitric oxide, so long as the amount of nitroxyldonation exceeds the amount of nitric oxide donation. In certainembodiments, a N-hydroxysulfonamide type nitroxyl donor useful in apharmaceutical composition of the disclosure can donate about 25 mole %or less of nitric oxide under physiological conditions. In particularembodiments, a N-hydroxysulfonamide type nitroxyl donor useful in apharmaceutical composition of the disclosure can donate about 20 mole %or less of nitric oxide under physiological conditions. In particularembodiments, a N-hydroxysulfonamide type nitroxyl donor useful in apharmaceutical composition of the disclosure can donate about 15 mole %or less of nitric oxide under physiological conditions. In particularembodiments, a N-hydroxysulfonamide type nitroxyl donor useful in apharmaceutical composition of the disclosure donating compound candonate about 10 mole % or less of nitric oxide under physiologicalconditions. In particular embodiments, a N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition of the disclosurecan donate about 5 mole % or less of nitric oxide under physiologicalconditions. In particular embodiments, a N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition of the disclosurecan donate about 2 mole % or less of nitric oxide under physiologicalconditions. In a particular embodiment, a N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition of the disclosurecan donate an insignificant amount (e.g., about 1 mole % or less) ofnitric oxide under physiological conditions.

Particular embodiments of N-hydroxysulfonamide type nitroxyl donorsuseful in pharmaceutical compositions of the disclosure are provided inTable 1 and Table 2. The compounds listed in Table 1 have been developedto optimize the half-life and toxicological profile of the nitroxyldonor, in accordance with one of the goals of the present disclosure.Compounds listed in Table 2 have previously been described (see, e.g.,U.S. Pat. No. 8,030,356, the contents of which are hereby incorporatedby reference in their entirety). The compounds listed in Table 1 andTable 2 generally have half-lives of greater than 10 minutes whenmeasured in an aerated phosphate buffered saline (PBS) solution and/orin plasma (see Table 4 in Section 5.2).

TABLE 1 Representative Novel N-Hydroxysulfonamide Compounds of theDisclosure

  N-Hydroxy-5-methylfuran-2- sulfonamide (1)

  N-Hydroxy-3- methanesulfonylbenzene- 1-sulfonamide (2)

  N-Hydroxy-5-methyl- 1,2-oxazole-4- sulfonamide (3)

  N-Hydroxy-1- benzofuran-7- sulfonamide (4)

  4-(Hydroxysulfamoyl)-N-(propan-2- yl)thiophene-2-carboxamide (5)

  N-Hydroxy-1-benzofuran-3- sulfonamide (6)

  N-Hydroxy-5-methyl-2- (trifluoromethyl)furan-3- sulfonamide (7)

  N-Hydroxy-5- methanesulfonylthiophene-3- sulfonamide (8)

  1-Acetyl-5-bromo-N-hydroxy-2,3- dihydro-1H-indole-6-sulfonamide (9)

  2-Chloro-N-hydroxy-5- (hydroxymethyl)benzene- 1-sulfonamide (10)

  1-Acetyl-5-chloro-N-hydroxy-2,3- dihydro-1H-indole-6-sulfonamide (11)

  4,5-Dichloro-N-hydroxythiophene- 2-sulfonamide (12)

  N-Hydroxy-6-methoxy-1-benzofuran-2- sulfonamide (13)

  2-Fluoro-N- hydroxy-4- methylbenzene-1- sulfonamide (14)

  N-Hydroxy-2,1,3- benzothiadiazole-5- sulfonamide (15)

  N-Hydroxy-4- methanesulfonylthiophene-2- sulfonamide (16)

  5-Bromo-N-hydroxy-2- methoxybenzene-1- sulfonamide (17)

  4-Chloro-N-hydroxy-2,5- dimethylbenzene-1- sulfonamide (18)

  N,N-Diethyl-5-(hydroxysulfamoyl)thiophene- 2-carboxamide (19)

  5-Fluoro-N-hydroxy-2- methylbenzene-1- sulfonamide (20)

  N-Hydroxy-5-(morpholine-4- carbonyl)thiophene-2-sulfonamide (21)

  5-(Hydroxysulfamoyl)-N-(propan- 2-yl)thiophene-2-carboxamide (22)

  N-Hydroxy-5- methanesulfonylthiophene- 2-sulfonamide (23)

  N-Hydroxy-2,1,3- benzothiadiazole-4- sulfonamide (24)

  N-Hydroxy-2- methoxybenzene-1- sulfonamide (25)

  N-Hydroxypyridine-3- sulfonamide (26)

  N-Hydroxy-3,5-dimethyl- 1,2-oxazole-4-sulfonamide (27)

  N-Hydroxy-5-(morpholine-4- carbonyl)thiophene-3-sulfonamide (28)

  1-N-Hydroxy-2-N-(propan-2- yl)benzene-1,2-disulfonamide (29)

  5-Chloro-N-hydroxy- 1,3-dimethyl-1H- pyrazole-4-sulfonamide (30)

  N-Hydroxy-1- methyl-1H- pyrazole-4- sulfonamide (31)

  N-Hydroxypyridine- 2-sulfonamide (32)

  3-Bromo-N- hydroxypyridine- 2-sulfonamide (33)

  4-N-Hydroxythiophene-2,4- disulfonamide (34)

  N-Hydroxy-4-(morpholine-4- carbonyl)thiophene-2-sulfonamide (35)

  N-Hydroxy-5-[5-(trifluoromethyl)-1,2-oxazol-3-yl]thiophene-2-sulfonamide (36)

  6-Chloro-N-hydroxy- 7H,7aH- imidazo[2,1-b][1,3] thiazole-5-sulfonamide(37)

  N-Hydroxy-5-(1,2-oxazol-5- yl)thiophene-2-sulfonamide (38)

  4-Fluoro-N-hydroxy- 2-methylbenzene- 1-sulfonamide (39)

  N-Hydroxy-5-(1,3-oxazol-5- yl)thiophene-2-sulfonamide (40)

  N-Hydroxy-2,5- dimethylthiophene-3- sulfonamide (41)

  Methyl 5-(hydroxysulfamoyl)-4- methylthiophene-2-carboxylate (42)

  5-(Benzenesulfonyl)-N- hydroxythiophene-2-sulfonamide (43)

  N-Hydroxy-5-(1,2-oxazol-3- yl)thiophene-2-sulfonamide (44)

  5-Bromo-N-hydroxythiophene- 2-sulfonamide (45)

  3,5-Dibromo-N- hydroxythiophene-2- sulfonamide (46)

  5-Chloro-N-hydroxy-4- nitrothiophene-2-sulfonamide (47)

  3-Chloro-N- hydroxythiophene-2- sulfonamide (48)

  N-Hydroxy-2,5- dimethylbenzene-1- sulfonamide (49)

  5-Chloro-N-hydroxy- 2,1,3-benzoxadiazole-4- sulfonamide (50)

  4-(Benzenesulfonyl)-N- hydroxythiophene-2-sulfonamide (51)

  N-Hydroxy-3,4- dimethoxybenzene- 1-sulfonamide (52)

  N-Hydroxy-2,3,5,6- tetramethylbenzene-1- sulfonamide (53)

  N-Hydroxy-3,5- bis(trifluoromethyl)benzene- 1-sulfonamide (54)

  Methyl 4-chloro-3- (hydroxysulfamoyl)benzoate (55)

  2-Fluoro-N-hydroxy-5- methylbenzene-1- sulfonamide (56)

  4-Chloro-N-(3-chloropropyl)-3- (hydroxysulfamoyl)-benzamide (57)

  2-Chloro-N-hydroxy-5-[4- (hydroxyimino)piperidine-1-carbonyl]benzene-1-sulfonamide (58)

  4-Chloro-3-(hydroxysulfamoyl)-N- (2-methoxyethyl)-N-methylbenzamide(59)

  2-Hydroxy-5- (hydroxysulfamoyl)benzoic acid (60)

  N-Hydroxy-4-methyl-3,4- dihydro-2H-1,4-benzoxazine- 7-sulfonamide (61)

  2-Chloro-N,4- dihydroxybenzene- 1-sulfonamide (62)

  3,5-Dichloro-N,4- dihydroxybenzene-1- sulfonamide (63)

  4-Chloro-2-hydroxy-5- (hydroxysulfamoyl)-N,N- dimethylbenzamide (64)

  5-Chloro-N-hydroxy-1-methyl- 2,3-dihydro-1H-indole-6- sulfonamide (65)

  2-Chloro-N,5- dihydroxybenzene-1- sulfonamide (66)

  5-Bromo-N-hydroxy-1-methyl- 2,3-dihydro-1H-indole-6- sulfonamide (67)

  2-Chloro-N-hydroxy-5- (methoxymethyl)benzene- 1-sulfonamide (68)

  Methyl 5-(hydroxysulfamoyl)furan-2- carboxylate (69)

  N-Hydroxy-2,5-dimethylfuran-3- sulfonamide (70)

  N-Hydroxy-8-oxatricyclo[7.4.0.0]trideca-1(9),2(7),3,5,10,12-hexaene-4-sulfonamide (71)

  2-(Ethanesulfonyl)-N- hydroxybenzene-1- sulfonamide (72)

  N-Hydroxy-2-(propane-2- sulfonyl)benzene-1- sulfonamide (73)

  4-Acetyl-N-hydroxy-3,4- dihydro-2H-1,4-benzoxazine- 6-sulfonamide (74)

  Methyl 5-(hydroxysulfamoyl)-1- methyl-1H-pyrrole-2-carboxylate (75)

  N-[5- (Hydroxysulfamoyl)- 1,3-thiazol-2- yl]acetamide (76)

  N-Hydroxy-2,5-dimethyl- 4-(morpholine-4- carbonyl)furan-3- sulfonamide(77)

  Ethyl 5-(hydroxysulfamoyl)furan- 3-carboxylate (78)

  5-Chlorothiophene-2- sulfonamidooxane-4-carboxylate (79)

  N-Hydroxy-2-(oxan-4- ylmethanesulfonyl)benzene- 1-sulfonamide (80)

  N-Hydroxy-3- methyl-1-benzofuran- 2-sulfonamide (81)

  N-Hydroxy-5-(piperidine-1- carbonyl)furan-2-sulfonamide (82)

TABLE 2 Additional N-Hydroxysulfonamide Donors with Desired Half-Lives

  N-Hydroxyfuran-2- sulfonamide (83)

  N-Hydroxy-5-methylthiophene- 2-sulfonamide (84)

  N-Hydroxy-1- methyl-1H-pyrazole- 3-sulfonamide (85)

  5-Chloro-N- hydroxythiophene-2- sulfonamide (86)

  3-Chloro-4- fluoro-N- hydroxybenzene- 1-sulfonamide (87)

  1-N,3-N-Dihydroxybenzene-1,3- disulfonamide (88)

  3-Bromo-N- hydroxybenzene-1- sulfonamide (89)

  5-Fluoro-N-hydroxy-2- methylbenzene-1- sulfonamide (90)

  N-Hydroxy-3,5-dimethyl- 1,2-oxazole-4- sulfonamide (91)

  N-Hydroxy-3- (trifluoromethoxy) benzene-1- sulfonamide (92)

  N-Hydroxy-4- methanesulfonyl- benzene-1- sulfonamide (93)

  2,5-Dichloro-N- hydroxybenzene-1- sulfonamide (94)

  3,4-Dichloro-N- hydroxybenzene- 1-sulfonamide (95)

  2- (Hydroxysulfamoyl)benzoic acid (96)

  3,5-Dichloro-N,2- dihydroxybenzene-1- sulfonamide (97)

In certain embodiments, the nitroxyl donors listed in Table 1 and Table2 can be converted into a pharmaceutically acceptable salt thereof.Representative salts include, but are not limited, to oxalate, chloride,bromide, iodide, sulfate, citrate, acetate, trifluoroacetate, nitrate,bisulfate, phosphate, acid phosphate, isonicotinate, lactate, glutamate,salicylate, acid citrate, tartrate, oleate, tannate, pantothenate,bitartrate, ascorbate, succinate, maleate, gentisinate, fumarate,gluconate, glucoronate, saccharate, formate, benzoate, methanesulfonate,ethanesulfonate, benzenesulfonate, p-toluenesulfonate, and pamoatesalts.

In some embodiments, the N-hydroxyl group of the compounds listed inTables 1 and 2 can be esterified to produce compounds of the generalformula (99), indicated below:

where

represents the aromatic, heteroaromatic or polycyclic portion of thecompounds depicted in Tables 1 and 2—including the substituents(s)depicted in Tables 1 and 2, if any —and where R is hydrogen,—(C₁-C₆)alkyl, —(C₂-C₄)alkenyl, phenyl, benzyl, cyclopentyl, cyclohexyl,—(C₅-C₇)heterocycloalkyl, benzyloxy, —O—(C₁-C₆)alkyl, —NH₂,—NH—(C₁-C₄)alkyl, or —N((C₁-C₄)alkyl)₂, wherein said —(C₁-C₆)alkyl,—(C₂-C₄)alkenyl, phenyl, benzyl, cyclopentyl, cyclohexyl,—(C₅-C₇)heterocycloalkyl, benzyloxy, —NH—(C₁-C₄)alkyl, or—N((C₁-C₄)alkyl)₂ can be unsubstituted or substituted with one or moresubstituents selected from halo, (C₁-C₆)alkyl, —(C₂-C₄)alkenyl,—(C₂-C₃)alkynyl, —(5- or 6-membered)heteroaryl, —O—(C₁-C₆)alkyl,—C(halo)₃, —CH(halo)₂, —CH₂(halo), —CN, —NO₂, —NH₂, —NH—(C₁-C₄)alkyl,—N(—(C₁-C₄)alkyl)₂, —C(═O)(C₁-C₄)alkyl, —C(═O)O(C₁-C₄)alkyl,—OC(═O)(C₁-C₄)alkyl, —OC(═O)NH₂, —S(═O)(C₁-C₄)alkyl, or—S(═O)₂(C₁-C₄)alkyl. In particular embodiments, R is methyl, ethyl,benzyl, or phenyl. In particular embodiments, R is methyl or ethyl. Inparticular embodiments, R is methyl. In particular embodiments, R isethyl. In particular embodiments, R is benzyl or phenyl. In particularembodiments, R is benzyl. In particular embodiments, R is phenyl.

4.3 Measuring Nitroxyl Donating Ability

Compounds are easily tested for nitroxyl donation by routineexperiments. Because it is typically impractical to directly measurewhether nitroxyl is donated, several analytical approaches are acceptedas suitable proxies for determining whether a compound donates nitroxyl.For example, the compound of interest can be placed in solution, forexample in phosphate buffered saline (PBS) or in a phosphate bufferedsolution at a pH of about 7.4, in a sealed container. After sufficienttime for disassociation has elapsed, such as from several minutes toseveral hours, the headspace gas is withdrawn and analyzed to determineits composition, such as by gas chromatography and/or mass spectrometry.If the gas N₂O is formed (which occurs by HNO dimerization), the test ispositive for nitroxyl donation and the compound is deemed to be anitroxyl donor.

For compounds in which the N-hydroxyl group of a N-hydroxysulfonamidetype nitroxyl donor is esterified, porcine liver esterase (PLE) can beadded to the stock solution used to perform the headspace analysis.

If desired, nitroxyl donation also can be detected by exposing the testcompound to metmyoglobin (Mb³⁺). See Bazylinski et al., J. Amer. Chem.Soc. 107(26):7982-7986 (1985). Nitroxyl reacts with Mb³⁺ to form aMb²⁺—NO complex, which can be detected by changes in theultraviolet/visible spectrum or by electron paramagnetic resonance(EPR). The Mb²⁺—NO complex has an EPR signal centered around a g-valueof about 2. Nitric oxide, on the other hand, reacts with Mb³⁺ to form anMb³⁺—NO complex that has a negligible, if any, EPR signal. Accordingly,if a compound reacts with Mb³⁺ to form a complex detectable by commonmethods, such as ultraviolet/visible or EPR, then the test is positivefor nitroxyl donation.

4.4 Pharmaceutical Compositions

The disclosure encompasses pharmaceutical compositions comprising anitroxyl donor and at least one pharmaceutically acceptable excipient.Examples of pharmaceutically acceptable excipients include thosedescribed above, such as carriers, surface active agents, thickening oremulsifying agents, solid binders, dispersion or suspension aids,solubilizers, colorants, flavoring agents, coatings, disintegratingagents, lubricants, sweeteners, preservatives, isotonic agents, and anycombination thereof. The selection and use of pharmaceuticallyacceptable excipients is taught, e.g., in Troy, Ed., Remington: TheScience and Practice of Pharmacy, 21^(st) Ed. (Lippincott Williams &Wilkins, Baltimore, Md., 2005).

The pharmaceutical compositions can be formulated for administration insolid or liquid form, including those adapted for the following: (1)oral administration, for example, as drenches (for example, aqueous ornon-aqueous solutions or suspensions), tablets (for example, thosetargeted for buccal, sublingual and systemic absorption), caplets,boluses, powders, granules, pastes for application to the tongue, hardgelatin capsules, soft gelatin capsules, mouth sprays, troches,lozenges, pellets, syrups, suspensions, elixirs, liquids, emulsions andmicroemulsions; or (2) parenteral administration by, for example,subcutaneous, intramuscular, intravenous or epidural injection as, forexample, a sterile solution or suspension. The pharmaceuticalcompositions can be for immediate, sustained or controlled release.

The compounds and pharmaceutical compositions disclosed herein can beprepared as any appropriate unit dosage form, such as capsules, sachets,tablets, powder, granules, solution, suspension in an aqueous liquid,suspension in a non-aqueous liquid, oil-in-water liquid emulsion,water-in-oil liquid emulsion, liposomes or bolus.

4.4.1 Compositions for Parenteral Administration

The disclosure provides nitroxyl donating compositions for parenteral(e.g., intravenous) administration. In one embodiment, thepharmaceutical composition is formulated for intravenous administrationby continuous infusion.

Various embodiments of pharmaceutical compositions suitable forparenteral administration include, without limitation, either aqueoussterile injection solutions or non-aqueous sterile injection solutions,each containing, for example, anti-oxidants, buffers, bacteriostats andsolutes that render the formulation isotonic with the blood of theintended recipient; and aqueous sterile suspensions and non-aqueoussterile suspensions, each containing, for example, suspending agents andthickening agents. The formulations can be presented in unit-dose ormulti-dose containers, for example, sealed ampules or vials, and can bestored in a freeze dried (lyophilized) condition requiring only theaddition of a sterile liquid carrier, such as water, immediately priorto use. Alternately, the formulation can be in the form of a liquid.

Pharmaceutical compositions administered parenterally can beadministered in an acidic, neutral or basic solution. In one embodiment,pharmaceutical compositions comprising a nitroxyl donor can beformulated in an acidic solution having a pH of from about 4 to about 5,for instance, a pH of about 4, about 4.5, about 4.8, or about 5,including values there between. While a pH of about 4 has generally beenconsidered optimal for formulating N-hydroxysulfonamide type nitroxyldonors in order to achieve adequate stability of the donor, it has beendiscovered that formulating under such acidic conditions can potentiallycause or exacerbate venous irritation following parenteraladministration. The amount of irritation can be attenuated byformulating the N-hydroxysulfonamide type nitroxyl donors in a lessacidic medium (see Example 6 and FIG. 4).

Accordingly, in certain embodiments, a N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition of the disclosureis formulated for parenteral injection at a pH of from about 5 to about6.5 in some embodiments, from about 5 to about 6 in some embodiments,from about 5.5 to about 6 in some embodiments, from about 5 to about 5.5in some embodiments, from about 5.2 to about 6.2 in some embodiments,from about 5.5 to about 6.2 in some embodiments, from about 5.8 to about6.2 in some embodiments, and at a pH of about 6 in particularembodiments. In another embodiment, a N-hydroxysulfonamide type nitroxyldonor useful in a pharmaceutical composition of the disclosure isformulated for parenteral injection at a pH of about 5.

To achieve the desired pH of the pharmaceutical composition, aN-hydroxysulfonamide type nitroxyl donor can be formulated in an aqueousbuffer. For example, a N-hydroxysulfonamide type nitroxyl donor can beformulated in a phosphate or acetate buffer. In particular embodiments,a N-hydroxysulfonamide type nitroxyl donor is formulated in a potassiumphosphate or sodium phosphate buffer. In other embodiments, aN-hydroxysulfonamide type nitroxyl donor is formulated in a potassiumphosphate buffer or sodium phosphate buffer. In other embodiments, aN-hydroxysulfonamide type nitroxyl donor is formulated in a potassiumcitrate buffer or sodium citrate buffer.

The aqueous buffer can also include an appropriate sugar in order tomaintain an appropriate osmolality. For instance, the pharmaceuticalcomposition can include an appropriate amount of dextrose. Thepharmaceutical compositions exemplified in the Examples of thedisclosure were generally prepared by diluting a concentrate comprisinga N-hydroxysulfonamide type nitroxyl donor, optionally a cyclodextrin(see Section 4.4.3) and an appropriate buffer into an aqueous solutioncomprising 5% dextrose (D5W) or 2.5% dextrose (D2.5W).

4.4.2 Compositions for Oral Administration

Pharmaceutical compositions comprising N-hydroxysulfonamide typenitroxyl donors can be formulated for oral administration. Compounds fororal administration can be formulated as liquid or solid dosage forms.In particular embodiments where the nitroxyl donors are formulated asoral liquid dosage forms, polyethylene glycol 300 (PEG300) can usefullyserve as an excipient.

Tablets for oral administration can be made by compression or molding,optionally with one or more accessory ingredients. Compressed tabletscan be prepared by compressing in a suitable machine the therapeuticagent or agents in a free-flowing form such as a powder or granules,optionally mixed with a binder, lubricant, inert diluent, preservative,surface-active or dispersing agent. Molded tablets can be made bymolding in a suitable machine a mixture of the powdered compoundmoistened with an inert liquid diluent. The tablets can be optionallycoated or scored and can be formulated so as to provide slow orcontrolled release of the active ingredient therein. Methods offormulating such slow or controlled release compositions ofpharmaceutically active ingredients, such as the therapeutic agentsherein and other compounds known in the art, are known in the art anddisclosed in issued U.S. patents, some of which include, but are notlimited to, U.S. Pat. Nos. 4,369,174, 4,842,866, and the referencescited therein. Coatings can be used for delivery of compounds to theintestine (see, e.g., U.S. Pat. Nos. 6,638,534, 5,217,720, 6,569,457,and the references cited therein). An artisan will recognize that inaddition to tablets, other dosage forms can be formulated to provideslow or controlled release of the active ingredient. Such dosage formsinclude, but are not limited to, capsules, granulations and gel-caps.

4.4.3 Stabilizing and Solubility Enhancing Agents

It has been discovered that N-hydroxysulfonamide type nitroxyl donorscan suffer from stability problems when formulated for parenteral andoral administration. In particular, the N-hydroxysulfonamide typenitroxyl donors gradually release nitroxyl and at least one byproduct inthe pharmaceutical composition, which can compromise the efficacy andsafety of the composition. For instance, compounds of formula (1) andformula (2) release nitroxyl and sulfinic acid byproducts (respectively,compounds of formula (100) and formula (101)) according to the followingschemes.

Moreover, N-hydroxysulfonamide type nitroxyl donors can also havesolubility problems that limit or preclude their use in an oral orparenteral dosage form. Accordingly, increasing the stability andsolubility of N-hydroxysulfonamide type nitroxyl donors can be importantbefore the donors can be used in therapeutic applications.

In accordance with one aspect of the disclosure, it has been found thatcyclodextrins can be used to dramatically enhance the stability and/orsolubility of N-hydroxysulfonamide type nitroxyl donors. Specifically,the cyclodextrins can mitigate or eliminate the formation of nitroxyland sulfinic acid byproducts (e.g., compounds of formula (100) and(101)) in a pharmaceutical composition during storage prior toadministration to a patient. The presence of the cyclodextrin alsoallows some of the N-hydroxysulfonamide type nitroxyl donors to bestabilized at a higher pH (e.g. pH of between 5 and 6), which, forreasons discussed in Section 4.4.2, results in the production of acomposition with an improved toxicological profile.

In various embodiments, the at least one pharmaceutically acceptableexcipient comprises at least one species of cyclodextrin. In aparticular embodiment, the cyclodextrin is a cyclic structure havingglucose units linked by a(1-4) linkages. In another embodiment, thecyclodextrin is a β-cyclodextrin, i.e., a cyclic structure having sevenglucose units linked by α(1-4) linkages. In another embodiment, thecyclodextrin is chemically modified by derivatizing any combination ofthe three available hydroxyl groups on each glucopyranose unit thereof.

In some embodiments where the pharmaceutically acceptable excipientcomprises at least one species of cyclodextrin, the cyclodextrin is asulfo(C₁-C₆)alkyl ether derivative of β-cyclodextrin. In certain ofthese embodiments, the cyclodextrin is a sulfo(C₁-C₆)alkyl etherderivative of β-cyclodextrin having from about six to about sevensulfo(C₁-C₆)alkyl ether groups per cyclodextrin molecule. In variousembodiments, the cyclodextrin is a sulfo(C₁-C₆)alkyl ether derivative ofβ-cyclodextrin having an average of from about six to about sevensulfo(C₁-C₆)alkyl ether groups per cyclodextrin molecule. In anothersuch embodiment, the cyclodextrin is a sulfo(C₁-C₆)alkyl etherderivative of β-cyclodextrin having six or seven sulfo(C₁-C₆)alkyl ethergroups per cyclodextrin molecule.

In a particular series of embodiments where the pharmaceuticallyacceptable excipient comprises at least one species of cyclodextrin, thecyclodextrin is a sulfo(C₃-C₅)alkyl ether derivative of β-cyclodextrin.In one such embodiment, the cyclodextrin is a sulfo(C₃-C₅)alkyl etherderivative of β-cyclodextrin having from about six to about sevensulfo(C₃-C₅)alkyl ether groups per cyclodextrin molecule. In varioussuch embodiments, the cyclodextrin is a sulfo(C₃-C₅)alkyl etherderivative of β-cyclodextrin having an average of from about six toabout seven sulfo(C₃-C₅)alkyl ether groups per cyclodextrin molecule. Inanother such embodiment, the cyclodextrin is a sulfo(C₃-C₅)alkyl etherderivative of β-cyclodextrin having six or seven sulfo(C₃-C₅)alkyl ethergroups per cyclodextrin molecule.

In particular embodiments where the pharmaceutically acceptableexcipient comprises at least one species of cyclodextrin, thecyclodextrin is a sulfobutyl ether derivative of β-cyclodextrin. Incertain of these embodiments, the cyclodextrin is a sulfobutyl etherderivative of β-cyclodextrin having from about six to about sevensulfobutyl ether groups per cyclodextrin molecule. In another suchembodiment, the cyclodextrin is a sulfobutyl ether derivative ofβ-cyclodextrin having an average of from about six to about sevensulfobutyl ether groups per cyclodextrin molecule. In another suchembodiment, the cyclodextrin is a sulfobutyl ether derivative ofβ-cyclodextrin having six or seven sulfobutyl ether groups percyclodextrin molecule.

In certain embodiments where the pharmaceutically acceptable excipientcomprises at least one species of cyclodextrin, the cyclodextrin is asulfo-n-butyl ether derivative of β-cyclodextrin. In one suchembodiment, the cyclodextrin is a sulfo-n-butyl ether derivative ofβ-cyclodextrin having from about six to about seven sulfo-n-butyl ethergroups per cyclodextrin molecule. In another such embodiment, thecyclodextrin is a sulfo-n-butyl ether derivative of β-cyclodextrinhaving an average of from about six to about seven sulfo-n-butyl ethergroups per cyclodextrin molecule. In another such embodiment, thecyclodextrin is a sulfo-n-butyl ether derivative of β-cyclodextrinhaving six or seven sulfo-n-butyl ether groups per cyclodextrinmolecule.

In various particular embodiments where the pharmaceutically acceptableexcipient comprises at least one species of cyclodextrin, thecyclodextrin comprises a plurality of negative charges atphysiologically compatible pH values, e.g., at a pH of from about 5.0 toabout 6.8 in some embodiments, from about 5.5 to about 6.5 in someembodiments, from about 5.7 to about 6.3 in some embodiments, from about5.8 to about 6.2 in some embodiments, from about 5.9 to about 6.1 insome embodiments, and about 6.0 in particular embodiments. In one suchembodiment, the at least one pharmaceutically acceptable excipientcomprises CAPTISOL® cyclodextrin (Ligand Pharmaceuticals, La Jolla,Calif.).

The molar ratio between the N-hydroxysulfonamide type nitroxyl donor andthe cyclodextrin present in the composition can be from about 0.02:1 toabout 2:1. In certain embodiments, the molar ratio between theN-hydroxysulfonamide type nitroxyl donor and the cyclodextrin present inthe composition can be from about 0.05:1 to about 1.5:1. In certainembodiments, the molar ratio between the N-hydroxy sulfonamide typenitroxyl donor and the cyclodextrin present in the composition can befrom about 0.1:1 to about 1:1. In certain embodiments, the molar ratiobetween the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition can be from about 0.5:1 to about1:1. In certain embodiments, the molar ratio between theN-hydroxysulfonamide type nitroxyl donor and the cyclodextrin present inthe composition can be in from about 0.7:1 to about 1:1. In certainembodiments, the molar ratio between the N-hydroxy sulfonamide typenitroxyl donor and the cyclodextrin present in the composition can befrom about 0.1:1 to about 0.8:1. In certain embodiments, the molar ratiobetween the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition can be from about 0.1:1 to about0.6:1. In certain embodiments, the molar ratio between theN-hydroxysulfonamide type nitroxyl donor and the cyclodextrin present inthe composition can be from about 0.2:1 to about 1:1. In certainembodiments, the molar ratio between the N-hydroxysulfonamide typenitroxyl donor and the cyclodextrin present in the composition can befrom about 0.2:1 to about 0.8:1. In certain embodiments, the molar ratiobetween the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition can be from about 0.4:1 to about0.8:1. In certain embodiments, the molar ratio between theN-hydroxysulfonamide type nitroxyl donor and the cyclodextrin present inthe composition can be from about 0.4:1 to about 0.6:1. In particularembodiments, the cyclodextrin is CAPTISOL®. For the purposes ofcalculating molar amounts, it will be assumed that CAPTISOL® has anaverage molecular weight (MW) of 2163 g/mol.

In embodiments where a N-hydroxysulfonamide type nitroxyl donor isadministered parenterally (e.g., intravenously) as an aqueouscomposition, the cyclodextrin can be present in the composition withinthe range of from about 0.001% cyclodextrin (w/v) to about 10%cyclodextrin (w/v). In some embodiments, the cyclodextrin can be presentin the composition within the range of from about 0.005% cyclodextrin(w/v) to about 8% cyclodextrin (w/v). In certain embodiments, thecyclodextrin can be present in the composition within the range of fromabout 0.010% cyclodextrin (w/v) to about 6% cyclodextrin (w/v). Incertain embodiments, the cyclodextrin can be present in the compositionwithin the range of from about 0.5% cyclodextrin (w/v) to about 8%cyclodextrin (w/v). In certain embodiments, the cyclodextrin can bepresent in the composition within the range of from about 1%cyclodextrin (w/v) to about 8% cyclodextrin (w/v). In certainembodiments, the cyclodextrin can be present in the composition withinthe range of from about 2% cyclodextrin (w/v) to about 8% cyclodextrin(w/v). In certain embodiments, the cyclodextrin can be present in thecomposition within the range of from about 2% cyclodextrin (w/v) toabout 6% cyclodextrin (w/v). In particular embodiments, the cyclodextrinis CAPTISOL®.

As described in Example 7, compositions comprising a nitroxyl donor anda cyclodextrin can be prepared as a concentrate at a particular pH. Sucha concentrate can be prepared by adding the nitroxyl donor to an aqueoussolution of the cyclodextrin at a particular pH (e.g., pH of 4). Theconcentrate can then be diluted into an appropriate aqueous solution(e.g., buffer) and administered to a patient. Alternatively, theconcentrate comprising the nitroxyl donor and the cyclodextrin can belyophilized to form a powder. The lyophilized powder can bereconstituted in the appropriate aqueous vehicle prior toadministration.

4.5 Methods of Using the Compounds and Pharmaceutical Compositions ofthe Disclosure

In one aspect, the disclosure provides a method of increasing in vivonitroxyl levels, comprising administering to a patient in need thereofan effective amount of a compound or a pharmaceutical composition asdisclosed herein. In various embodiments, the patient has, is suspectedof having, or is at risk of having or developing a condition that isresponsive to nitroxyl therapy.

In particular embodiments, the disclosure provides a method of treating,preventing or delaying the onset and/or development of a condition,comprising administering to a patient (including a patient identified asin need of such treatment, prevention or delay) an effective amount of acompound or a pharmaceutical composition as disclosed herein.Identifying a patient in need thereof can be in the judgment of aphysician, clinical staff, emergency response personnel or other healthcare professional and can be subjective (e.g., opinion) or objective(e.g., measurable by a test or diagnostic method).

Particular conditions embraced by the methods disclosed herein include,without limitation, cardiovascular diseases, ischemia/reperfusioninjury, and pulmonary hypertension (PH).

4.5.1 Cardiovascular Diseases

In one embodiment, the disclosure provides a method of treating acardiovascular disease, comprising administering an effective amount ofa compound or a pharmaceutical composition as disclosed herein to apatient in need thereof.

Examples of cardiovascular diseases and symptoms that can usefully betreated with the compounds and compositions disclosed herein includecardiovascular diseases that are responsive to nitroxyl therapy,coronary obstructions, coronary artery disease (CAD), angina, heartattack, myocardial infarction, high blood pressure, ischemiccardiomyopathy and infarction, pulmonary congestion, pulmonary edema,cardiac fibrosis, valvular heart disease, pericardial disease,circulatory congestive states, peripheral edema, ascites, Chagas'disease, ventricular hypertrophy, heart valve disease, heart failure,diastolic heart failure, systolic heart failure, congestive heartfailure, acute congestive heart failure, acute decompensated heartfailure, and cardiac hypertrophy.

4.5.1.1 Heart Failure

The nitroxyl donating compositions of the disclosure can be used totreat patients suffering from heart failure. The heart failure can be ofany type or form, including any of the heart failures disclosed herein.Nonlimiting examples of heart failure include early stage heart failure,Class I, II, III and IV heart failure, acute heart failure, congestiveheart failure (CHF) and acute congestive heart failure. In oneembodiment, the compounds and compositions of the disclosure can be usedto treat acute decompensated heart failure.

In embodiments where the nitroxyl donating compositions of thedisclosure are used to treat patients suffering from heart failure,another active agent that treats heart failure can also be administered.In one such embodiment, the nitroxyl donor can be administered inconjunction with a positive inotrope such as a beta-agonist. Examples ofbeta-agonists include, without limitation, dopamine, dobutamine,isoproterenol, analogs of such compounds and derivatives of suchcompounds. In another embodiment, nitroxyl donor can be administered inconjunction with a beta-adrenergic receptor antagonist (also referred toherein as beta-antagonist or beta-blocker). Examples of beta-antagonistsinclude, without limitation, propranolol, metoprolol, bisoprolol,bucindolol, and carvedilol.

As described in Example 3, a heart failure model was used to evaluatethe hemodynamic profiles of compositions comprising several of thelonger half-life nitroxyl donors. As shown in FIG. 1, which arediscussed in Example 3, the compositions of the disclosure producedsignificant enhancement of inotropy and lusitropy, and modest reductionsin blood pressure without tachycardia. Moreover, the onset ofsignificant hemodynamic effects was rapid (e.g., within 1 hour) and forall compositions near-maximal effect was achieved within 2 hours.

While the hemodynamic activity of compositions of the disclosure aresimilar to compositions comprising the nitroxyl donor CXL-1020 whenadministered intravenously, the toxicological profile of theN-hydroxysulfonamide type nitroxyl donors, which have longer half-livesthan CXL-1020, is significantly improved as compared to compositionscomprising CXL-1020 (see Examples 5 and 6 and FIGS. 2-4). For example,the “No Observed Adverse Effect Levels” (NOAEL) of nitroxyl donorsuseful in compositions of the disclosure were substantially higher thanthe NOAEL for CXL-1020 (see Example 5 for description of NOAELdetermination). In particular; the compound of formula (1) has the mostfavorable toxicological profile of all N-hydroxysulfonamide typenitroxyl donors tested thus far and shows no adverse effects on clinicalmarkers of inflammation when administered intravenously atconcentrations at least as high as 30 μg/kg/min (FIG. 2). In contrast,CXL-1020 begins to show undesirable side effects at concentrations aslow as 0.3 μg/kg/min.

4.5.1.2 Ischemia/Reperfusion Injury

In another embodiment, the disclosed subject matter provides a method oftreating, preventing or delaying the onset and/or development ofischemia/reperfusion injury, comprising administering an effectiveamount of a compound or pharmaceutical composition as disclosed hereinto a subject in need thereof.

In a particular embodiment, the method is for preventingischemia/reperfusion injury. In a particular embodiment, apharmaceutical composition of the disclosure is administered prior tothe onset of ischemia. In a particular embodiment, a pharmaceuticalcomposition of the disclosure is administered prior to procedures inwhich myocardial ischemia can occur, for example an angioplasty orsurgery, such as a coronary artery bypass graft surgery. In a particularembodiment, a pharmaceutical composition of the disclosure isadministered after ischemia but before reperfusion. In a particularembodiment, a pharmaceutical composition of the disclosure isadministered after ischemia and reperfusion.

In a another embodiment, a pharmaceutical composition of the disclosurecan be administered to a patient who is at risk for an ischemic event.In a particular embodiment, a pharmaceutical composition of thedisclosure is administered to a patient at risk for a future ischemicevent, but who has no present evidence of ischemia. The determination ofwhether a patient is at risk for an ischemic event can be performed byany method known in the art, such as by examining the patient or thepatient's medical history. In a particular embodiment, the patient hashad a prior ischemic event. Thus, the patient can be at risk of a firstor subsequent ischemic event. Examples of patients at risk for anischemic event include patients with known hypercholesterolemia, EKGchanges associated with ischemia (e.g., peaked or inverted T-waves or STsegment elevations or depression in an appropriate clinical context),abnormal EKG not associated with active ischemia, elevated CKMB,clinical evidence of ischemia (e.g., crushing sub-sternal chest pain orarm pain, shortness of breath and/or diaphoresis), prior history ofmyocardial infarction, elevated serum cholesterol, sedentary lifestyle,angiographic evidence of partial coronary artery obstruction,echocardiographic evidence of myocardial damage, or any other evidenceof a risk for a future ischemic event. Examples of ischemic eventsinclude, without limitation, myocardial infarction (MI) andneurovascular ischemia, such as a cerebrovascular accident (CVA).

In another embodiment, the subject of treatment is an organ that is tobe transplanted. In a particular embodiment, a pharmaceuticalcomposition of the disclosure can be administered prior to reperfusionof the organ in a transplant recipient. In a particular embodiment, apharmaceutical composition of the disclosure can be administered priorto removal of the organ from the donor, for example through theperfusion cannulas used in the organ removal process. If the organ donoris a live donor, for example a kidney donor, the compounds orpharmaceutical compositions of the disclosure can be administered to theorgan donor. In a particular embodiment, the compounds or pharmaceuticalcompositions of the disclosure are administered by storing the organ ina solution comprising the compound or pharmaceutical composition. Forexample, a compound or pharmaceutical composition of the disclosure canbe included in the organ preservation solution, such as the Universityof Wisconsin “UW” solution, which is a solution comprising hydroxyethylstarch substantially free of ethylene glycol, ethylene chlorohydrin andacetone (see U.S. Pat. No. 4,798,824). In a particular embodiment, apharmaceutical composition of the disclosure that is administered issuch that ischemia/reperfusion injury to the tissues of the organ isreduced upon reperfusion in the recipient of transplanted organ. In aparticular embodiment, the method reduces tissue necrosis (the size ofinfarct) in at-risk tissues.

Ischemia/reperfusion injury can damage tissues other than those of themyocardium and the disclosed subject matter embraces methods of treatingor preventing such damage. In various embodiments, theischemia/reperfusion injury is non-myocardial. In particularembodiments, the method reduces injury from ischemia/reperfusion in thetissue of the brain, liver, gut, kidney, bowel, or any part of the bodyother than the myocardium. In another embodiment, the patient is at riskfor such injury. Selecting a person at risk for non-myocardial ischemiacould include a determination of the indicators used to assess risk formyocardial ischemia. However, other factors can indicate a risk forischemia/reperfusion in other tissues. For example, surgery patientsoften experience surgery related ischemia. Thus, patients scheduled forsurgery could be considered at risk for an ischemic event. The followingrisk factors for stroke (or a subset of these risk factors) coulddemonstrate a patient's risk for ischemia of brain tissue: hypertension,cigarette smoking, carotid artery stenosis, physical inactivity,diabetes mellitus, hyperlipidemia, transient ischemic attack, atrialfibrillation, coronary artery disease, congestive heart failure, pastmyocardial infarction, left ventricular dysfunction with mural thrombus,and mitral stenosis. Ingall, Postgrad. Med. 107(6):34-50 (2000).Further, complications of untreated infectious diarrhea in the elderlycan include myocardial, renal, cerebrovascular and intestinal ischemia.Slotwiner-Nie et al., Gastroenterol. Gin. N. Amer. 30(3):625-635 (2001).Alternatively, patients could be selected based on risk factors forischemic bowel, kidney and/or liver disease. For example, treatmentwould be initiated in elderly patients at risk of hypotensive episodes(such as surgical blood loss). Thus, patients presenting with such anindication would be considered at risk for an ischemic event. In anotherembodiment, the patient has any one or more of the conditions listedherein, such as diabetes mellitus and hypertension. Other conditionsthat can result in ischemia, such as cerebral arteriovenousmalformation, could demonstrate a patient's risk for an ischemic event.

4.5.2 Pulmonary Hypertension

In another embodiment, a pharmaceutical composition of the disclosurecan be used to prevent or delay the onset and/or development ofpulmonary hypertension. In one such embodiment, a pharmaceuticalcomposition of the disclosure can be used to prevent or delay the onsetand/or development of pulmonary arterial hypertension (PAH).

In another embodiment, the disclosure provides a method of reducing meanpulmonary arterial pressure (MPAP), comprising administering aneffective amount of a compound or a pharmaceutical composition disclosedherein to a patient in need thereof. In another embodiment, the MPAP isreduced by up to about 50%. In another embodiment, the MPAP is reducedby up to about 25%. In another embodiment, the MPAP is reduced by up toabout 20%. In another embodiment, the MPAP is reduced by up to about15%. In another embodiment, the MPAP is reduced by up to 10%. In anotherembodiment, the MPAP is reduced by up to about 5%. In anotherembodiment, the MPAP is reduced to be from about 12 mmHg to about 16mmHg. In another embodiment, the MPAP is reduced to be about 15 mmHg.

4.6 Administration Modes, Regimens and Dose Levels

The compounds and pharmaceutical compositions of the disclosure can beadministered via parenteral (e.g., subcutaneous, intramuscular,intravenous or intradermal) administration. In certain embodiments, theN-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure is administered by intravenous infusion.In other embodiments, the compounds and pharmaceutical compositions ofthe disclosure can be administered by oral administration.

When a pharmaceutical composition comprising a compound of the presentdisclosure is administered, dosages are expressed based on the amount ofactive pharmaceutical ingredient, i.e., the amount of nitroxyl donorcompound(s) of the disclosure present in the pharmaceutical composition.

For intravenous administration, the dose can usefully be expressed perunit time, either as a fixed amount per unit time or as a weight-basedamount per unit time.

In various embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredintravenously in an amount of at least about 0.1 μg/kg/min, at leastabout 0.2 μg/kg/min, at least about 0.3 μg/kg/min, at least about 0.4μg/kg/min, at least about 0.5 μg/kg/min, at least about 1 μg/kg/min, atleast about 2.5 μg/kg/min, at least about 5 μg/kg/min, at least about7.5 mg/kg/min, at least about 10 μg/kg/min, at least about 11 μg/kg/min,at least about 12 μg/kg/min, at least about 13 μg/kg/min, at least about14 μg/kg/min, at least about 15 mg/kg/min, at least about 16 μg/kg/min,at least about 17 μg/kg/min, at least about 18 μg/kg/min, at least about19 mg/kg/min, at least about 20 μg/kg/min, at least about 21 μg/kg/min,at least about 22 μg/kg/min, at least about 23 μg/kg/min, at least about24 μg/kg/min, at least about 25 μg/kg/min, at least about 26 μg/kg/min,at least about 27 μg/kg/min, at least about 28 μg/kg/min, at least about29 μg/kg/min, at least about 30 μg/kg/min, at least about 31 μg/kg/min,at least about 32 μg/kg/min, at least about 33 μg/kg/min, at least about34 μg/kg/min, at least about 35 μg/kg/min, at least about 36 μg/kg/min,at least about 37 μg/kg/min, at least about 38 μg/kg/min, at least about39 μg/kg/min, or at least about 40 μg/kg/min.

In various embodiments, the N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredintravenously in an amount of no more than about 100 μg/kg/min, no morethan about 90 μg/kg/min, no more than about 80 μg/kg/min, no more thanabout 70 μg/kg/min, no more than about 60 μg/kg/min, no more than about50 μg/kg/min, no more than about 49 μg/kg/min, no more than about 48μg/kg/min, no more than about 47 μg/kg/min, no more than about 46μg/kg/min, no more than about 45 μg/kg/min, no more than about 44μg/kg/min, no more than about 43 μg/kg/min, no more than about 42μg/kg/min, no more than about 41 μg/kg/min, no more than about 40μg/kg/min, no more than about 39 μg/kg/min, no more than about 38μg/kg/min, no more than about 37 μg/kg/min, no more than about 36μg/kg/min, no more than about 35 μg/kg/min, no more than about 34μg/kg/min, no more than about 33 μg/kg/min, no more than about 32μg/kg/min, no more than about 31 μg/kg/min, or no more than about 30μg/kg/min

In some embodiments, the N-hydroxysulfonamide type nitroxyl donor usefulin a pharmaceutical composition of the disclosure is administeredintravenously in an amount ranging from about 0.1 μg/kg/min to about 100μg/kg/min, about 1 μg/kg/min to about 100 μg/kg/min, about 2.5 μg/kg/minto about 100 μg/kg/min, about 5 μg/kg/min to about 100 μg/kg/min, about10 μg/kg/min to about 100 μg/kg/min, about 1.0 μg/kg/min to about 80μg/kg/min, from about 10.0 μg/kg/min to about 70 μg/kg/min, from about20 μg/kg/min to about 60 μg/kg/min, from about 15 μg/kg/min to about 50μg/kg/min, from about 0.01 μg/kg/min to about 1.0 μg/kg/min, from about0.01 μg/kg/min to about 10 μg/kg/min, from about 0.1 μg/kg/min to about1.0 μg/kg/min, from about 0.1 μg/kg/min to about 10 μg/kg/min, fromabout 1.0 μg/kg/min to about 5 μg/kg/min, from about 70 μg/kg/min toabout 100 μg/kg/min, or from about 80 μg/kg/min to about 90 μg/kg/min.

In particular embodiments, the N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredintravenously in an amount ranging from about 10 μg/kg/min to about 50μg/kg/min, about 20 μg/kg/min to about 40 μg/kg/min, about 25 μg/kg/minto about 35 μg/kg/min, or about 30 μg/kg/min to about 40 μg/kg/min. Inparticular embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredintravenously in an amount of from about 20 μg/kg/min to about 30μg/kg/min.

In a variety of embodiments, including various oral administrationembodiments, the compounds or pharmaceutical compositions of thedisclosure are administered according to a weight-based daily dosingregimen, either as a single daily dose (QD) or in multiple divided dosesadministered, e.g., twice a day (BID), three times a day (TID), or fourtimes a day (QID).

In certain embodiments, the nitroxyl donating N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition of the disclosureis administered in a dose of at least about 0.5 mg/kg/d, at least about0.75 mg/kg/d, at least about 1.0 mg/kg/d, at least about 1.5 mg/kg/d, atleast about 2 mg/kg/d, at least about 2.5 mg/kg/d, at least about 3mg/kg/d, at least about 4 mg/kg/d, at least about 5 mg/kg/d, at leastabout 7.5 mg/kg/d, at least about 10 mg/kg/d, at least about 12.5mg/kg/d, at least about 15 mg/kg/d, at least about 17.5 mg/kg/d, atleast about 20 mg/kg/d, at least about 25 mg/kg/d, at least about 30mg/kg/d, at least about 35 mg/kg/d, at least about 40 mg/kg/d, at leastabout 45 mg/kg/d, at least about 50 mg/kg/d, at least about 60 mg/kg/d,at least about 70 mg/kg/d, at least about 80 mg/kg/d, at least about 90mg/kg/d, or at least about 100 mg/kg/d.

In certain embodiments, the nitroxyl donating N-hydroxysulfonamide typenitroxyl donor useful in a pharmaceutical composition of the disclosureis administered at a dose of no more than about 100 mg/kg/d, no morethan about 100 mg/kg/d, no more than about 90 mg/kg/d, no more thanabout 80 mg/kg/d, no more than about 80 mg/kg/d, no more than about 75mg/kg/d, no more than about 70 mg/kg/d, no more than about 60 mg/kg/d,no more than about 50 mg/kg/d, no more than about 45 mg/kg/d, no morethan about 40 mg/kg/d, no more than about 35 mg/kg/d, no more than about30 mg/kg/d.

In a variety of embodiments, the dose is from about 0.001 mg/kg/d toabout 10,000 mg/kg/d. In certain embodiments, the dose is from about0.01 mg/kg/d to about 1,000 mg/kg/d. In certain embodiments, the dose isfrom about 0.01 mg/kg/d to about 100 mg/kg/d. In certain embodiments,the dose is from about 0.01 mg/kg/d to about 10 mg/kg/d. In certainembodiments, the dose is from about 0.1 mg/kg/d to about 1 mg/kg/d. Incertain embodiments, the dose is less than about 1 g/kg/d.

In certain embodiments, a N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredin a dose range in which the low end of the range is any amount fromabout 0.1 mg/kg/day to about 90 mg/kg/day and the high end of the rangeis any amount from about 1 mg/kg/day to about 100 mg/kg/day (e.g., fromabout 0.5 mg/kg/day to about 2 mg/kg/day in one series of embodimentsand from about 5 mg/kg/day to about 20 mg/kg/day in another series ofembodiment).

In particular embodiments, the N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredin a dose range of about 3 to about 30 mg/kg, administered from once aday (QD) to three times a day (TID).

In certain embodiments, compounds or pharmaceutical compositions of thedisclosure are administered according to a flat (i.e., non-weight-based)dosing regimen, either as a single daily dose (QD) or in multipledivided doses administered, e.g., twice a day (BID), three times a day(TID), or four times a day (QID).

In various embodiments, the N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredat a dose of at least about 0.01 grams/day (g/d), at least about 0.05g/d, at least about 0.1 g/d, at least about 0.5 g/d, at least about 1g/d, at least about 1.5 g/d, at least about 2.0 g/d, at least about 2.5g/d, at least about 3.0 g/d, or at least about 3.5 g/d.

In various embodiments, the N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredat a dose of no more than about 5 g/d, no more than about 4.5 g/d, nomore than about 4 g/d, no more than about 3.5 g/d, no more than about 3g/d, no more than about 2.5 g/d, or no more than about 2 g/d.

In certain embodiments, the N-hydroxysulfonamide type nitroxyl donoruseful in a pharmaceutical composition of the disclosure is administeredin a dose of about 0.01 grams per day to about 4.0 grams per day. Incertain embodiments, a N-hydroxysulfonamide type nitroxyl donor usefulin a pharmaceutical composition of the disclosure can be administered ata dose in which the low end of the range is any amount from about 0.1mg/day to about 400 mg/day and the high end of the range is any amountfrom about 1 mg/day to about 4000 mg/day. In certain embodiments, theN-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure is administered in a dose of about 5mg/day to about 100 mg/day. In various embodiments, theN-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure is administered at a dose of from about150 mg/day to about 500 mg/day.

The dosing interval for parenteral or oral administration can beadjusted according to the needs of the patient. For longer intervalsbetween administrations, extended release or depot formulations can beused.

A N-hydroxysulfonamide type nitroxyl donor useful in a pharmaceuticalcomposition of the disclosure as disclosed herein can be administeredprior to, at substantially the same time with, or after administrationof an additional therapeutic agent. The administration regimen caninclude pretreatment and/or co-administration with the additionaltherapeutic agent. In such case, the N-hydroxysulfonamide type nitroxyldonor useful in a pharmaceutical composition of the disclosure and theadditional therapeutic agent can be administered simultaneously,separately, or sequentially.

Examples of administration regimens include without limitation:administration of each compound, pharmaceutical composition ortherapeutic agent in a sequential manner; and co-administration of eachcompound, pharmaceutical composition or therapeutic agent in asubstantially simultaneous manner (e.g., as in a single unit dosageform) or in multiple, separate unit dosage forms for each compound,pharmaceutical composition or therapeutic agent.

It will be appreciated by those in the art that the “effective amount”or “dose” (“dose level”) will depend on various factors such as theparticular administration mode, administration regimen, compound, andpharmaceutical composition selected, as well as the particular conditionand patient being treated. For example, the appropriate dose level canvary depending upon the activity, rate of excretion and potential fortoxicity of the specific N-hydroxysulfonamide type nitroxyl donor usefulin a pharmaceutical composition of the disclosure employed; the age,body weight, general health, gender and diet of the patient beingtreated; the frequency of administration; the other therapeutic agent(s)being co-administered; and the type and severity of the condition.

4.7 Kits Comprising the Compounds or Pharmaceutical Compositions

The disclosure provides kits comprising a compound or a pharmaceuticalcomposition disclosed herein. In a particular embodiment, the kitcomprises a compound or a pharmaceutical composition disclosed herein,each in dry form, and a pharmaceutically acceptable liquid diluent.

Either a compound in dry form or a pharmaceutical composition in dryform contains about 2.0% or less water by weight, about 1.5% or lesswater by weight, about 1.0% or less water by weight, about 0.5% or lesswater by weight, about 0.3% or less water by weight, about 0.2% or lesswater by weight, about 0.1% or less water by weight, about 0.05% or lesswater by weight, about 0.03% or less water by weight, or about 0.01% orless water by weight.

Pharmaceutically acceptable liquid diluents are known in the art andinclude but are not limited to sterile water, saline solutions, aqueousdextrose, glycerol, glycerol solutions, and the like. Other examples ofsuitable liquid diluents are disclosed by Nairn, “Solutions, Emulsions,Suspensions and Extracts,” pp. 721-752 in Gennaro, Ed., Remington: TheScience and Practice of Pharmacy, 20th Ed. (Lippincott Williams &Wilkins, Baltimore, Md., 2000).

In one embodiment, the kit further comprises instructions for using thecompound or pharmaceutical composition. The instructions can be in anyappropriate form, such as written or electronic form. In anotherembodiment, the instructions can be written instructions. In anotherembodiment, the instructions are contained in an electronic storagemedium (e.g., magnetic diskette or optical disk). In another embodiment,the instructions include information as to the compound orpharmaceutical composition and the manner of administering the compoundor pharmaceutical composition to a patient. In another embodiment, theinstructions relate to a method of use disclosed herein (e.g., treating,preventing and/or delaying onset and/or development of a conditionselected from cardiovascular diseases, ischemia/reperfusion injury,pulmonary hypertension and other conditions responsive to nitroxyltherapy).

In another embodiment, the kit further comprises suitable packaging.Where the kit comprises more than one compound or pharmaceuticalcomposition, the compounds or pharmaceutical compositions can bepackaged patiently in separate containers, or combined in one containerwhen cross-reactivity and shelf life permit.

5. EXAMPLES

The following examples are presented for illustrative purposes andshould not serve to limit the scope of the disclosed subject matter.

5.1 Example 1 HNO Production as Determined via N₂O Quantification

Nitrous oxide (N₂O) is produced via the dimerization and dehydration ofHNO, and is the most common marker for nitroxyl production (Fukuto etal., Chem. Res. Toxicol. 18:790-801 (2005)). Nitroxyl, however, can alsobe partially quenched by oxygen to provide a product that does notproduce N₂O (see Mincione et al., J. Enzyme Inhibition 13:267-284(1998); and Scozzafava et al., J. Med. Chem. 43:3677-3687 (2000)). Usingeither nitrous oxide gas or Angeli's salt (AS) as a standard, therelative amounts of N₂O released from compounds of the disclosure wasexamined via gas chromatography (GC) headspace analysis.

A procedure for determining the relative amounts of N₂O released fromcompounds of the disclosure is as follows. GC was performed on anAgilent gas chromatograph equipped with a split injector (10:1splitting), microelectron capture detector, and a HP-MOLSIV 30 m×0.32mm×25 μm molecular sieve capillary column. Helium was used as thecarrier (4 mL/min) gas and nitrogen was used as the make-up (20 mL/min)gas. The injector oven and the detector oven were kept at 200° C. and325° C., respectively. All nitrous oxide analyses were performed withthe column oven held at a constant temperature of 200° C.

All gas injections were made using an automated headspace analyzer. Vialpressurization was 15 psi. The analyzer's sample oven, sampling valve,and transfer line were kept at 40° C., 45° C., and 50° C., respectively.The oven stabilization, vial pressurization, loop fill, loopequilibration, and sample injection times were 1.00 min., 0.20 min.,0.20 min., 0.05 min., and 1.00 min., respectively.

All determinations used a batch of nominal 20 mL headspace vials withvolumes pre-measured for sample uniformity (actual vial volume varied by<2.0% relative standard deviation (n=6)). The average vial volume forthe batch was determined from six randomly-selected vials by calculatingthe weight difference between the capped and sealed empty (i.e.,air-filled) vial and the capped and sealed deionized water-filled vialusing the known density of deionized water, then averaging. Blanks wereprepared by sealing and capping two vials then purging each for 20seconds with a gentle argon stream. Nitroxyl standards were prepared bysealing and capping four vials then purging each for 1 minute with agentle stream, from a gas cylinder, of a 3000 ppm nitroxyl standard.

CXL-1020 (N-hydroxy-2-methanesulfonylbenzene-1-sulfonamide) “standards”were prepared by, in duplicate, accurately weighing 10±0.5 mg ofCXL-1020 and adding it to each 4 mL vial. Using an auto pipette, 1 mL ofargon-purged anhydrous DMF (Sigma-Aldrich) was added to each 4 mL vialto form a CXL-1020 stock solution for each sample and the vials werecapped and shaken and/or sonicated to insure complete dissolution uponvisual observation. Using an auto pipette, 20 mL vials were charged with5 mL of PBS (purged for at least 30 min. with argon prior to use),purged with argon for at least 20 sec., and sealed with a rubber septum.Using a 50 μL syringe, 50 μL of the CXL-1020 stock solution was injectedinto each 20 mL vial containing the PBS.

Samples were prepared as follows. In duplicate, 18±1 mg of each samplewas accurately weighed into each 4 mL vial. Using an auto pipette, 1 mLof argon-purged anhydrous DMF was added to each 4 mL vial to form asample stock solution for each sample and the vials were capped andshaken and/or sonicated to insure complete sample dissolution uponvisual observation. Using an auto pipette, 20 mL vials were charged with5 mL of PBS (purged for at least 30 min. with argon prior to use),purged with argon for at least 20 sec., and sealed with a rubber septum.The vials were equilibrated for at least 10 min. at 37° C. in a dryblock heater. Thereafter, using a 50 μL syringe, 50 μL of a sample stocksolution was injected into each 20 mL vial containing the PBS. The vialswere then held at 37° C. in the dry block heater for a time period suchthat the sum of the time spent in the dry block heater plus the timespent in the automated headspace analyzer oven before sample injectionequaled the desired incubation time.

The sequence for auto-injection was as follows: blank replicate 1, blankreplicate 2, N₂O standard replicate 1, N₂O standard replicate 2,CXL-1020 standard replicate 1, CXL-1020 standard replicate 2, sample 1replicate 1, sample 1 replicate 2, sample 2 replicate 1, sample 2replicate 2, etc., concluding with N₂O standard replicate 3, and N₂Ostandard replicate 4. An EXCEL spreadsheet is used for inputting datathus determined and calculating, for each sample, the relative N₂O yieldin percent for each incubation time. The results obtained are providedin Table 3. “-” indicates that results were not determined.

TABLE 3 Results of N₂O Headspace Analysis Relative N₂O Relative N₂OYield Yield Compound (90 minutes (360 minutes No. Compound incubation)incubation)  1 N-Hydroxy-5-methylfuran-2-sulfonamide 52% —  2N-Hydroxy-3-methanesulfonylbenzene-1- 82% 94% sulfonamide  3N-Hydroxy-5-methyl-1,2-oxazole-4- 45% 56% sulfonamide  4N-Hydroxy-1-benzofuran-7 sulfonamide 64% —  54-(Hydroxysulfamoyl)-N-(propan-2- 48% 72% yl)thiophene-2-carboxamide  6N-Hydroxy-1-benzofuran-3-sulfonamide 85% —  7N-Hydroxy-5-methyl-2-(trifluoromethyl)furan- 51% — 3-sulfonamide  8N-Hydroxy-5-methanesulfonylthiophene-3- 77% — sulfonamide  91-Acetyl-5-bromo-N-hydroxy-2,3-dihydro-1H- 53% 71% indole-6-sulfonamide10 2-Chloro-N-hydroxy-5- 91% — (hydroxymethyl)benzene-1-sulfonamide 111-Acetyl-5-chloro-N-hydroxy-2,3-dihydro-1H- 55% 81% indole-6-sulfonamide12 4,5-Dichloro-N-hydroxythiophene-2- 29% — sulfonamide 13N-Hydroxy-6-methoxy-1-benzofuran-2- 86% — sulfonamide 142-Fluoro-N-hydroxy-4-methylbenzene-1- 48% 70% sulfonamide 15N-Hydroxy-2,1,3-benzothiadiazole-5- 59% 71% sulfonamide 16N-Hydroxy-4-methanesulfonylthiophene-2- 86% — sulfonamide 175-Bromo-N-hydroxy-2-methoxybenzene-1- 53% 77% sulfonamide 184-Chloro-N-hydroxy-2,5-dimethylbenzene-1- 56% 73% sulfonamide 19N,N-Diethyl-5-(hydroxysulfamoyl)thiophene- 77% — 2-carboxamide 205-Fluoro-N-hydroxy-2-methylbenzene-1- 90% — sulfonamide 21N-Hydroxy-5-(morpholine-4- 73.5%   — carbonyl)thiophene-2-sulfonamide 225-(Hydroxysulfamoyl)-N-(propan-2- 85% — yl)thiophene-2-carboxamide 24N-Hydroxy-2,1,3-benzothiadiazole-4- 60% 69% sulfonamide 25N-Hydroxy-2-methoxybenzene-1-sulfonamide  7% 28% 26N-Hydroxypyridine-3-sulfonamide 73.5%   — 27N-Hydroxy-3,5-dimethyl-1,2-oxazole-4- 35.5%   66% sulfonamide 28N-Hydroxy-5-(morpholine-4- 74% — carbonyl)thiophene-3-sulfonamide 305-Chloro-N-hydroxy-1,3-dimethyl-1H- 27% — pyrazole-4-sulfonamide 32N-Hydroxypyridine-2-sulfonamide 71% — 333-Bromo-N-hydroxypyridine-2-sulfonamide 85.5%   — 344-N-Hydroxythiophene-2,4-disulfonamide 100%  — 35N-Hydroxy-4-(morpholine-4- 100%  — carbonyl)thiophene-2-sulfonamide 36N-Hydroxy-5-[5-(trifluoromethyl)-1,2-oxazol- 51% —3-yl]thiophene-2-sulfonamide 37 6-Chloro-N-hydroxy-7H,7aH-imidazo[2,1-51% — b][1,3]thiazole-5-sulfonamide 38N-Hydroxy-5-(1,2-oxazol-5-yl)thiophene-2- 25% — sulfonamide 394-Fluoro-N-hydroxy-2-methylbenzene-1- 60% 75% sulfonamide 40N-Hydroxy-5-(1,3-oxazol-5-yl)thiophene-2- 50% — sulfonamide 41N-Hydroxy-2,5-dimethylthiophene-3- 13% — sulfonamide 42 Methyl5-(hydroxysulfamoyl)-4- 91% — methylthiophene-2-carboxylate 435-(Benzenesulfonyl)-N-hydroxythiophene-2- 82% — sulfonamide 44N-Hydroxy-5-(1,2-oxazol-3-yl)thiophene-2- 81% — sulfonamide 455-Bromo-N-hydroxythiophene-2-sulfonamide 76% — 463,5-Dibromo-N-hydroxythiophene-2- 95% — sulfonamide 475-Chloro-N-hydroxy-4-nitrothiophene-2- 58% 70% sulfonamide 483-Chloro-N-hydroxythiophene-2-sulfonamide 82% — 49N-Hydroxy-2,5-dimethylbenzene-1- 42% 68% sulfonamide 505-Chloro-N-hydroxy-2,1,3-benzoxadiazole-4- 31% — sulfonamide 514-(Benzenesulfonyl)-N-hydroxythiophene-2- 96% — sulfonamide 52N-Hydroxy-3,4-dimethoxybenzene-1- 11% — sulfonamide 53N-Hydroxy-2,3,5,6-tetramethylbenzene-1- 70% — sulfonamide 54N-Hydroxy-3,5-bis(trifluoromethyl)benzene-1-  2% — sulfonamide 55 Methyl4-chloro-3- 87% — (hydroxysulfamoyl)benzoate 56 2-Fluoro-N-hydroxy- 72%78% 5-methylbenzene-1-sulfonamide 58 2-Chloro-N-hydroxy-5-[4- 92% —(hydroxyimino)piperidine-1-carbonyl]benzene- 1-sulfonamide 594-Chloro-3-(hydroxysulfamoyl)-N-(2- 82% —methoxyethyl)-N-methylbenzamide 60 2-Hydroxy-5-(hydroxysulfamoyl)benzoicacid  9% — 61 N-Hydroxy-4-methyl-3,4-dihydro-2H-1,4- 11% —benzoxazine-7-sulfonamide 62 2-Chloro-N,4-dihydroxybenzene-1-sulfonamide28% — 64 4-Chloro-2-hydroxy-5-(hydroxysulfamoyl)- 36% —N,N-dimethylbenzamide 65 5-Chloro-N-hydroxy-1-methyl-2,3-dihydro-1H- 71%— indole-6-sulfonamide 66 2-Chloro-N,5-dihydroxybenzene-1-sulfonamide80% — 67 5-Bromo-N-hydroxy-1-methyl-2,3-dihydro-1H- 59% —indole-6-sulfonamide 68 2-Chloro-N-hydroxy-5- 86% —(methoxymethyl)benzene-1-sulfonamide 69 Methyl5-(hydroxysulfamoyl)furan-2- 100%  carboxylate 70N-Hydroxy-2,5-dimethylfuran-3-sulfonamide  6% — 722-(Ethanesulfonyl)-N-hydroxybenzene-1- 97% — sulfonamide 73N-Hydroxy-2-(propane-2-sulfonyl)benzene-1- 97% — sulfonamide 744-Acetyl-N-hydroxy-3,4-dihydro-2H-1,4- 17% — benzoxazine-6-sulfonamide75 Methyl 5-(hydroxysulfamoyl)-1-methyl-1H-  4% — pyrrole-2-carboxylate76 N-[5-(Hydroxysulfamoyl)-1,3-thiazol-2- 76% — yl]acetamide 77N-Hydroxy-2,5-dimethyl-4-(morpholine-4- 14% —carbonyl)furan-3-sulfonamide 78 Ethyl5-(hydroxysulfamoyl)furan-3-carboxylate 86% — 83N-Hydroxyfuran-2-sulfonamide 42% 86% 84N-Hydroxy-5-methylthiophene-2-sulfonamide 52% 67% 85N-Hydroxy-1-methyl-1H-pyrazole-3- 33.5%   — sulfonamide 873-Chloro-4-fluoro-N-hydroxybenzene-1- 53% 79% sulfonamide 881-N,3-N-Dihydroxybenzene-1,3-disulfonamide 53% 100%  905-Fluoro-N-hydroxy-2-methylbenzene-1- 90% — sulfonamide 92N-Hydroxy-3-(trifluoromethoxy)benzene-1- 59% — sulfonamide 93N-Hydroxy-4-methanesulfonylbenzene-1- 86% — sulfonamide

For compounds of formula (99), determinations are as described aboveexcept enzyme activated samples are also prepared as follows: (i)accurately weigh 50 mg of porcine liver esterase (PLE, E3019-20KU,crude, Sigma-Aldrich) into a 20 mL headspace vial; (ii) using an autopipette, 5 mL of argon-purged anhydrous PBS is added to form a PLE stocksolution; (iii) the vial is capped and shaken to insure completedissolution upon visual observation; (iv) samples of nitroxyl donors areprepared as disclosed above except 4.75 mL of PBS is added instead of 5mL; and (v) using an auto pipette, the 20 mL vials are then charged with250 μmL of PLE stock solution prior to sample addition. The sequence forauto-injection is as follows: blank replicate 1, blank replicate 2, N₂Ostandard replicate 1, N₂O standard replicate 2, CXL-1020 standardreplicate 1, CXL-1020 standard replicate 2, sample 1 (no PLE) replicate1, sample 1 (no PLE) replicate 2, sample 1 (with PLE) replicate 1,sample 1 (with PLE) replicate 2, sample 2 (no PLE) replicate 1, sample 2(no PLE) replicate 2, sample 2 (with PLE) replicate 1, sample 2 (withPLE) replicate 2, etc., concluding with N₂O standard replicate 3, andN₂O standard replicate 4.

Another procedure for determining the relative amounts of N₂O releasedfrom compounds of the disclosure is as follows. GC is performed on aVarian CP-3800 instrument equipped with a 1041 manual injector, electroncapture detector, and a 25 m 5 Å molecular sieve capillary column. Grade5.0 nitrogen is used as both the carrier (8 mL/min) and the make-up (22mL/min) gas. The injector oven and the detector oven are kept at 200° C.and 300° C., respectively. All nitrous oxide analyses are performed withthe column oven held at a constant temperature of 150° C. All gasinjections are made using a 100 μL gas-tight syringe with a sample-lock.Samples are prepared in 15 mL amber headspace vials with volumespre-measured for sample uniformity (actual vial volume ranges from 15.19to 15.20 mL). Vials are charged with 5 mL of PBS containingdiethylenetriamine pentaacetic anhydride (DTPA), purged with argon, andsealed with a rubber septum. The vials are equilibrated for at least 10minutes at 37° C. in a dry block heater. A 10 mM stock solution of AS isprepared in 10 mM sodium hydroxide, and solutions of the nitroxyl donorsare prepared in either acetonitrile or methanol and used immediatelyafter preparation. From these stock solutions, 50 μL is introduced intoindividual thermally-equilibrated headspace vials using a 100 μLgas-tight syringe with a sample-lock to provide final substrateconcentrations of 0.1 mM. Substrates are then incubated for 90 minutesor 360 minutes. The headspace (60 μL) is then sampled and injected fivesuccessive times into the GC apparatus using the gas-tight syringe witha sample lock. This procedure is repeated for two or more vials perdonor.

5.2 Example 2 In Vitro Stability of Nitroxyl Donors in Plasma

Certain compounds from Tables 1 and 2 and CXL-1020 were tested for theirstability in phosphate buffered saline (PBS) and plasma. The assaysystem comprised (i) PBS, or plasma from rat, dog or human (at least 3donors, male, pooled) at pH 7.4, and (ii) for tests conducted in plasma,an anticoagulant (sodium heparin or sodium citrate). Each test compound(5 μM) was incubated in PBS or plasma at 37° C. on a THERMOMIXER® withshaking. Three samples (n=3) were taken at each of seven sampling timepoints: 0, 10, 30, 60, 90, 180 and 360 minutes. The samples wereimmediately combined with 3 volumes (i.e., 3 times the volume of PBS orplasma) of acetonitrile containing 1% formic acid and an internalstandard to terminate the reaction. AB SCIEX API 3000 LC-MS/MS analysisof the test compounds was performed without a standard curve. Half-lives(T_(1/2)) of the test compounds were determined from graphs of thepercent remaining values using the peak area response ratio. Thehalf-lives determined are provided in Table 4. For compounds testedmultiple times, the value provided in the Table represents an average ofthe replicate assays.

TABLE 4 Half-lives (T_(1/2)) of Nitroxyl Donors T_(1/2) T_(1/2) T_(1/2)T_(1/2) Compound (minutes) (minutes) (minutes) (minutes) No. CompoundPBS Rat Dog Human CXL-1020 N-Hydroxy-2- 2 2 methanesulfonylbenzene-1-sulfonamide  1 N-Hydroxy-5-methylfuran-2- 68 40 25 65 sulfonamide  2N-Hydroxy-3- 50 20 33 37 methanesulfonylbenzene-1- sulfonamide  3N-Hydroxy-5-methyl-1,2- 98 37 38 71 oxazole-4-sulfonamide  4N-Hydroxy-1-benzofuran-7 149 sulfonamide  5 4-(Hydroxysulfamoyl)-N- 136104 28 24 (propan-2-yl)thiophene-2- carboxamide  7 N-Hydroxy-5-methyl-2-224 56 (trifluoromethyl)furan-3- sulfonamide  8 N-Hydroxy-5- 42 27methanesulfonylthiophene-3- sulfonamide  9 1-Acetyl-5-bromo-N-hydroxy-2 >360 2,3-dihydro-1H-indole-6- sulfonamide 10 2-Chloro-N-hydroxy-5- 5(hydroxymethyl)benzene-1- sulfonamide 11 1-Acetyl-5-chloro-N-hydroxy- 5<5 2,3-dihydro-1H-indole-6- sulfonamide 12 4,5-Dichloro-N- 20hydroxythiophene-2- sulfonamide 13 N-Hydroxy-6-methoxy-1- 42benzofuran-2-sulfonamide 14 2-Fluoro-N-hydroxy-4- 75 13methylbenzene-1-sulfonamide 15 N-Hydroxy-2,1,3- 63benzothiadiazole-5-sulfonamide 16 N-Hydroxy-4- 20methanesulfonylthiophene-2- sulfonamide 17 5-Bromo-N-hydroxy-2- 59 >360methoxybenzene-1-sulfonamide 18 4-Chloro-N-hydroxy-2,5- 56 >360dimethylbenzene-1-sulfonamide 19 N,N-Diethyl-5- 44(hydroxysulfamoyl)thiophene-2- carboxamide 20 5-Fluoro-N-hydroxy-2- 25 7methylbenzene-1-sulfonamide 21 N-Hydroxy-5-(morpholine-4- 39 36carbonyl)thiophene-2- sulfonamide 22 5-(Hydroxysulfamoyl)-N- 33 23(propan-2-yl)thiophene-2- carboxamide 23 N-Hydroxy-5- 66methanesulfonylthiophene-2- sulfonamide 24 N-Hydroxy-2,1,3- 37 14benzothiadiazole-4-sulfonamide 25 N-Hydroxy-2-methoxybenzene- 861-sulfonamide 26 N-Hydroxypyridine-3- 53 29 45 sulfonamide 27N-Hydroxy-3,5-dimethyl-1,2- 225 75 99 oxazole-4-sulfonamide 28N-Hydroxy-5-(morpholine-4- 136 carbonyl)thiophene-3- sulfonamide 305-Chloro-N-hydroxy-1,3- 385 dimethyl-1H-pyrazole-4- sulfonamide 31N-Hydroxy-1-methyl-1H- 745 pyrazole-4-sulfonamide 32N-Hydroxypyridine-2- 61 32 sulfonamide 35 N-Hydroxy-4-(morpholine-4- 5819 carbonyl)thiophene-2- sulfonamide 39 4-Fluoro-N-hydroxy-2- 30 29methylbenzene-1-sulfonamide 47 5-Chloro-N-hydroxy-4- 11 <5nitrothiophene-2-sulfonamide 49 N-Hydroxy-2,5- 87 13dimethylbenzene-1-sulfonamide 51 4-(Benzenesulfonyl)-N- 15 7hydroxythiophene-2- sulfonamide 56 2-Fluoro-N-hydroxy-5- 34 8methylbenzene-1-sulfonamide 83 N-Hydroxyfuran-2-sulfonamide 37 43 38 1684 N-Hydroxy-5-methylthiophene- 125 65 55 60 2-sulfonamide 85N-Hydroxy-1-methyl-1H- 59 72 pyrazole-3-sulfonamide 865-Chloro-N-hydroxythiophene- 38 12 18 2-sulfonamide 873-Chloro-4-fluoro-N- 101 49 24 hydroxybenzene-1-sulfonamide 881-N,3-N-Dihydroxybenzene-1,3- 38 16 disulfonamide 893-Bromo-N-hydroxybenzene-1- 76 38.4 34 sulfonamide 905-Fluoro-N-hydroxy-2- 25.1 6.8 21 methylbenzene-1-sulfonamide 91N-Hydroxy-3,5-dimethyl-1,2,- 211 176 54.4 oxazole-4-sulfonamide 92N-Hydroxy-3- 58 35 19 40 (trifluoromethoxy)benzene-1- sulfonamide 92N-Hydroxy-3- 57.9 35.1 18.5 (trifluoromethoxy)benzene-1- sulfonamide 93N-Hydroxy-4- 68 38 35 methanesulfonylbenzene-1- sulfonamide 953,4-Dichloro-N- >360 >360 hydroxybenzene-1-sulfonamide 953,4-Dichloro-N- >360 >360 hydroxybenzene-1-sulfonamide

For measuring half-lives of a compound of formula (99), a stock solutionof pig liver esterase (PLE) is added to the PBS or plasma prior toaddition of said compound.

5.3 Example 3 Hemodynamic Efficacy of Nitroxyl Donors in Normal andHeart Failure Canines (Tachycardia-Pacing Model)

5.3.1 Materials and Methods

The cardiovascular effects of nitroxyl donors were examined by means ofpressure-volume (PV) curve (loops) analysis in conscious,sling-restrained beagle dogs. Animals were allowed free access todrinking water and a commercial canine diet under standard laboratoryconditions. Fluorescent lighting was provided via an automatic timer forapproximately 12 hours per day. On occasion, the dark cycle wasinterrupted intermittently due to study-related activities. Temperatureand humidity were monitored and recorded daily and maintained to themaximum extent possible between 64° F. and 84° F. and 30% to 70%,respectively. The dogs were acclimated for a period of at least 1 weekprior to surgery. Following surgery and recovery the animals wereacclimated to sling restraint for a period up to 4.5 hours. Animals werefasted overnight prior to surgery.

Surgical Procedure

Anesthesia

An indwelling venous catheter was placed in peripheral vein (e.g.,cephalic) for administration of anesthetic. General anesthesia wasinduced intravenously (bolus) with buprenorphine (about 0.015 mg/kg)followed by an intravenous bolus of propofol (about 6 mg/kg).Additionally, a prophylactic antibiotic (cefazolin 20 to 50 mg/kg viai.v.) was given upon induction. A cuffed tracheal tube was placed andused to ventilate mechanically the lungs with 100% 0₂ via avolume-cycled animal ventilator (about 12 breaths/minute with a tidalvolume of about 12.5 mL/kg) in order to sustain PaCO₂ values within thephysiological range. Anesthesia was maintained with inhaled isoflurane(1% to 3%).

Cardiovascular Instrumentation

Once a stable (surgical) plane of anesthesia had been established, aleft-thoracotomy was performed (under strict aseptic conditions) andeach animal was chronically instrumented with sono-micrometry crystalsproviding left-ventricular (LV) dimensions/volume. Additionally, afluid-filled catheter and a solid-state monometer were placed in theleft ventricle for pressure monitoring. A fluid-filled catheters wasplaced in the right ventricle (RV) and the aorta (Ao) for pressuremonitoring/test article administration. A hydraulic (In-Vivo Metrics)occluder was placed/secured around the inferior vena cava (IVC), inorder to allow its controlled constriction for the generation of LVpressure-volume curves during heterometric auto-regulation. Thecatheters/wires were aseptically tunneled and externalized between thescapulae. Over the course of the study, fluid-filled catheters wereregularly (at least once weekly) flushed with a locking-solution inorder to prevent both clotting and bacterial growth (2-3 mL ofTaurolidine-Citrate solution, TCS-04; Access Technologies).

Pacemaker Implantation

Following the cardiovascular instrumentation, the right jugular vein wascarefully exposed and cannulated with a bipolar pacing lead/catheter(CAP SUREFIX® Novus; Medtronic). Under fluoroscopic guidance, thispacing lead was advanced normograde into the right ventricle andactively affixed (screwed in) to the apical endocardium. The proximalend of the lead was secured to the pacing device (Kappa 900; Medtronic).Subsequently, the pacemaker was placed/secured in a subcutaneous pocketin the neck.

Considering that the heart was exposed via a thoracotomy, a bipolarpacing wire was secured in the right ventricular mid-myocardium. Thispacing lead was tunneled/externalized between the scapulae, and used inconjunction with an external impulse generator/pacemaker. The implantedendocardial pacemaker was used as a back-up to the external/epicardialpacemaker.

Recovery

Prior to closure of the chest from the thoracotomy, a chest tube wasplaced for drainage of any fluid and/or gas that accumulated from thesurgical procedure. The tube was aspirated twice daily until the amountof fluid removed was less than 35 mL per aspiration in an approximately24 hour period. The chest tube was then removed.

All animals were administered a prophylactic antibiotic (cefazolin 20 to50 mg/kg via i.v.) and pain medication (meloxicam at about 0.2 mg/kg viai.v.). If necessary, an additional analgesic was also administered whichincluded a fentanyl patch (25 to 50 mcg/hour). All surgical incisionswere closed in layers; the underlying musculature was closed withabsorbable sutures and the skin was closed with staples.

Following surgery, the animals were allowed to recover for at least 14days.

Cephalexin (20 to 50 mg/kg) was administered orally BID for at least 7days and meloxicam (0.1 mg/kg) was administered SID orally orsubcutaneously for at least 2 days after surgery. Throughout therecovery phase, the animals were observed daily for routine signs ofrecovery and the wound sites were observed for any signs of potentialinfections. Animals experiencing pain, distress and/or infections werebrought to the attention of the attending veterinarian and the studydirector. The skin incision staples were not removed for at least 7 daysafter surgery.

Induction of Heart Failure

Following a recovery from surgery and/or sufficient washout period fromdosing with a nitroxyl donor, animals were subjected to a 3-weekoverdrive pacing (210 ppm) protocol aimed to trigger left-ventriculardysfunction/remodeling consistent with the heart failure syndrome. Inshort, via the implanted pacemaker/right-ventricular lead, theventricle(s) was asynchronously and continuously paced at 210 beats perminute (bpm). Left-ventricular remodeling (and heart failure induction)were confirmed by both echocardiographic (e.g., ejection fraction EFdecrease from about 60% to a target of about 35%, left ventricular LVdilatation) and neuro-humoral (e.g., N-terminal pro-brain natriureticpeptide (NT proBNP) elevation to greater than 1800 pM/L from a baselineof about 300 pM/L) changes after approximately 3 weeks of pacing.Echocardiographs and blood samples were collected in the absence ofpacing (for at least 15 min).

5.3.2 Results

Hemodynamic Efficacy Assessments

The animals (normal or heart failure) were studied during treatment withboth vehicle (control) and a nitroxyl donor (either CXL-1020 or acompound of formula (1), (2) (83), (84) or (85)). At each dosing period,conscious sling-restrained animals were continuously monitored for up totwo to three hours. Following hemodynamic stabilization, infusion of thevehicle was started. Shortly thereafter, left-ventricular pre-load wasacutely reduced by means of brief vena cava occlusions (via transientinflation of the vessel occluder) in order to generate a family ofpressure-volume curves/loops; up to three occlusions were performed,allowing for hemodynamic recovery between tests. Infusion of the vehiclewas continued and after 30 min another (baseline) set of hemodynamicdata was collected. Following collection of baseline hemodynamic data,infusion of the nitroxyl donor compound being tested was initiated andtype hemodynamic/functional parameters were obtained/performed at up tofour (4) time points selected from the following: at 30, 60, 90, 120,and 180 minutes after the onset of vehicle/test compound infusion. Forthe placebo or time-control treatment group, each animal wasadministered an infusion of an appropriate placebo for up to 180minutes. In all cases, the test compound was delivered at a constantintravenous infusion rate of 1 mL/kg/hr and was compared at a molarequivalent or approximate two-thirds of a molar equivalent dose rate.

The resulting left-ventricular pressure and volume data were analyzed inorder to generate relationships representing the contractile andenergetic state of the myocardium. Systolic arterial pressure (SAP),diastolic arterial pressure (DAP), and mean arterial pressure (MAP) werecollected. Left-ventricular mechanical and/or geometrical indices wereobtained from the pressure (ESP, EDP, dP/dt max/min, time-constant ofrelaxation-tau [based on mono-exponential decay with non-zeroasymptote]) and volume (end-systolic volume (ESV), end diastolic volume(EDV), stroke volume (SV)) signal. In addition, the followingmeasurements were type from left-ventricular pressure-volume data (PVloops) generated during brief periods of preload reduction: pressurevolume area (PVA) and stroke work (SW), end-systolic (ESPVR) andend-diastolic (EDPVR) pressure volume relationships, and end systolicpressure and stroke volume relationship (arterial elastance (Ea)).Representative data obtained from studies in normal dogs and heartfailure dogs are shown in Table 5 and Table 6. Representative data forheart failure dogs are also shown in FIG. 1. An SVR (systemic vascularresistance) decrease correlates with vasodilation.

TABLE 5 Hemodynamic Parameters for Nitroxyl Donors in Normal Canines (%Change from Baseline) Compound Control CXL-1020 (1) (2) (83) (84) DoseRate 0 100 50 100 65 77 (μmol/kg/min) Number of 3 6 8 4 4 4 Animals HR−2.21 ± 1.51  6.71 ± 4.72 −4 ± 2 −6.17 ± 5.58  2.89 ± 2.94  4.31 ± 2.98ESP  −1.8 ± 0.58 −17.79 ± 3.09 −18 ± 2  −15.22 ± 2.39  −21.99 ± 3.32−16.85 ± 2.33 EDV  2.62 ± 0.42 −20.51 ± 7.63 −6 ± 2 −17.41 ± 1.58 −16.88 ± 1.69 −10.99 ± 2.33 Tau 11.14 ± 1.15  −6.58 ± 4.53 −6 ± 1 −6.40± 7.11 −10.10 ± 1.56  −9.60 ± 6.06 SW −2.80 ± 1.26 −13.96 ± 5.51 −11 ±4  −17.56 ± 2.66  −19.18 ± 6.70 −13.98 ± 1.14 ESPVR −3.20 ± 1.15  28.25± 8.69 19 ± 1 25.87 ± 5.04  29.33 ± 8.36  50.71 ± 8.14 PRSW −0.78 ± 0.38 12.60 ± 2.96 12 ± 1 12.88 ± 1.12  19.79 ± 3.39  17.70 ± 2.35Abbreviations: HR: Heart rate. Increased HR, either due to reflexresponse to low blood pressure or due to a primary drug effect on theheart, is bad. ESP: End systolic pressure - similar to MAP below. EDP orLVEDP: End diastolic pressure (left ventricular). Correlates withpulmonary pressures. A decrease indicates a reduction of pulmonarycongestion (a key objective of acute heart failure therapy). Tau: Anindex of lusitropy, or relaxation of the heart during diastole. Decreaseis positive and indicates improved diastolic performance. SW: Strokework. Measure of how much work the heart exerts to create a given amountof forward flow. ESPVR: End systolic pressure volume relationship. Ameasure of inotropy/contractility (a key objective of acute heartfailure therapy). Increases indicate improved cardiac performance andefficiency. PRSW: Preload recruitable stroke work - similar to ESPVRabove. SV: Stroke volume. The amount of blood ejected from the leftventricle with each beat of the heart. An inotrope should increase this,given identical loading conditions. MAP OR MBP: Mean arterial pressureor mean blood pressure. Small drops are positive and evidence ofvasodilation. EDV or LVEDV: End diastolic volume (left ventricular).Index of the degree of filling in diastole. A decrease indicates areduction in volume overload.

TABLE 6 Hemodynamic Parameters for Nitroxyl Donors in Heart FailureCanines (% Change from Baseline) Compound Control CXL-1020 (1) (2) (83)(84) Dose Rate 0 100 75 100 65 77 (μmol/kg/min) Number of Animals 3 6 64 4 4 ESP 3.89 ± 2.11 −14.78 ± 3.24 −17 ± 1  −13.83 ± 3.30  −18.52 ±2.59  −13.72 ± 2.83  HR −5.08 ± 5.83   −0.23 ± 2.25 −6 ± 2 −1.36 ± 2.06 0.05 ± 1.25  3.72 ± 2.45 EDV 0.86 ± 0.86 −12.03 ± 3.72 −9 ± 2 −3.26 ±1.05 −4.91 ± 0.57 −13.43 ± 4.63  SW 1.83 ± 1.87 −12.01 ± 4.24 10 ± 5−9.41 ± 2.84 −9.63 ± 1.70 −5.96 ± 1.58 Tau 4.05 ± 4.72 −17.27 ± 1.39 −16± 4  −12.51 ± 2.72  −18.32 ± 3.06  15.61 ± 1.58 ESPVR −3.14 ± 0.87  45.42 ± 16.48 29 ± 1 22.84 ± 5.69 38.06 ± 8.79 51.01 ± 5.85 PRSW −0.88± 0.68   21.97 ± 3.79 22 ± 1 17.91 ± 1.47 14.90 ± 2.27 25.03 ± 2.52Abbreviations: HR, heart rate; ESP, end systolic pressure; EDV, enddiastolic volume; Tau, time constant for relaxation; SW, stroke work;ESPVR, end systolic pressure volume relationship; PRSW, preloadrecruitable stroke work.

The results, e.g., in FIG. 1, demonstrate that compounds of formulas(1), (2), (83), (84) and (85) have comparable hemodynamic activity toCXL-1020 in both normal and failing canine models.

5.4 Toxicology Studies with Nitroxyl Donors 5.4.1 Example 4 In VivoTrials with CXL-1020

During in vivo trials of the nitroxyl donor CXL-1020(N-hydroxy-2-methanesulfonylbenzene-1-sulfonamide), a 14-day study wasconducted to evaluate tolerance in dogs treated with continuousinfusions of CXL-1020 at dose rates of up to 90 μg/kg/min.

This first study found that CXL-1020 was tolerated when administered ata dose rate of 60 μg/kg/min. Unexpectedly, however, clinical pathologychanges consistent with an inflammation process, as reflected in changesin clinical pathology markers of inflammation, were observed at the 60μg/kg/min dose rate. To further investigate this undesirableside-effect, a follow-up 14-day study in dogs was initiated. Thefollow-up study needed to be terminated after only 4 days due to theappearance of other undesirable side-effects: the unexpected occurrenceof significant swelling and inflammation in the dogs' hind limbs whereinfusion catheters had been surgically implanted, which occasionallyinterfered with normal limb function; skin discoloration in the inguinalregion; decreased activity; inappetance; and in the highest-dosagegroup, skin cold to the touch.

To determine the cause of the inflammation and hind limb swelling, aseries of 72-hour continuous infusion investigative studies wereconducted over the following 6 months. The results of those studiesshowed that CXL-1020, when administered in a pH 4 formulation of a 1:1molar ratio of CXL-1020:CAPTISOL®, diluted into a solution of 5%dextrose in water, caused clinical pathology changes consistent with aninflammatory process at dose rates greater than or equal to 0.03μg/kg/min in dogs. Vascular inflammation was observed around the site ofinsertion of the catheter into the femoral vein (15 cm upstream from thecatheter tip), at the catheter tip, and downstream from the cathetertip. The first site of inflammation, the catheter insertion site, causedthe dog hind limb swelling and inflammation observed in theearly-terminated follow-up study. Increasing infusate pH from 4 to 6decreased inflammation, improving the inflammatory profile byapproximately 3-fold (see FIG. 4). However, significant undesirable sideeffects were still demonstrated when CXL-1020 was administered at doserates greater than or equal to 3 μg/kg/min in the dogs.

To avoid the catheter insertion site-associated side effects and toassess whether the vascular inflammation was due to the design of theimplanted catheter, a 24-hour continuous infusion study was conducted indogs using a percutaneous catheter placed in a peripheral (cephalic)vein. After 6 hours of infusion, significant edema was observed in theupper forelimb, downstream from the catheter tip. After 24 hours ofinfusion, clinical pathology changes similar to those observed inprevious studies using an implanted central catheter were detected. Alsodetected was microscopic pathology demonstrating a severethrombophlebitis at the catheter tip and progressing with a gradient oflessening severity downstream from the catheter tip.

To determine whether a local phlebitis would occur in humans upon longerduration dosing, a longer duration study was conducted in healthyvolunteers. The longer duration study included a dose escalation studyin which cohorts of 10 volunteers were to be sequentially administered a24-hour continuous infusion of CXL-1020 at the dose rates of 10, 20, and30 μg/kg/min with a safety assessment between each cohort. Each cohortconsisted of 2 placebo and 8 active treatments with a sentinel pair of 1active and 1 placebo followed by the main group of 1 placebo and 7active treatments. The infusion was via a percutaneous catheter insertedinto a forearm vein. The catheter was switched to the contralateral armafter 12 hours of infusion. The dose rate of 10 μg/kg/min for 24-hourswas found to be well tolerated. In the second cohort, administered adose of 20 μg/kg/min for 24-hours, there were no adverse findings in the2 placebo-treated volunteers but there were mild findings (eitherclinical signs and/or changes in clinical pathology) in all 8 subjectsconsistent with infusion site phlebitis. Based on these results, thelonger duration safety study was halted.

Exploratory studies were continued to determine the cause of theundesirable side effects of CXL-1020 at the higher, but still clinicallydesirable, doses. Studies conducted with the byproduct of CXL-1020, themoiety that remains after nitroxyl donation, was negative, indicatingthat the CXL-1020's side effects were attributable to either the parentcompound, CXL-1020, or to the HNO produced therefrom. Studies wereconducted with alternative Nitroxyl donors that were structurallyunrelated to CXL-1020 but had similar half-lives for nitroxyl donation(half-lives of about 2 minutes). In all instances, local vascular sideeffects at the catheter tip were observed. These results suggested thatthe inflammation was caused by nitroxyl that was rapidly released fromthe short half-life nitroxyl donors.

5.4.2 Example 5 Longer Half-Life N-Hydroxysulfonamide Type NitroxylDonors Have an Improved Toxicological Profile Relative to CXL-1020

Studies were conducted in male and female beagle dogs. Animals wereallowed free access to drinking water and a commercial canine diet understandard laboratory conditions. Animals were fasted prior to bloodsample collections when indicated by the study protocol. Fluorescentlighting was provided via an automatic timer for approximately 12 hoursper day. On occasion, the dark cycle was interrupted intermittently dueto study-related activities. Temperature and humidity were monitored andrecorded daily and maintained to the maximum extent possible between 64°F. to 84° F. and 30% to 70%, respectively. The dogs were acclimated fora period of at least 1 week. During this period, the animals wereweighed weekly and observed with respect to general health and any signsof disease. The animals were acclimated to wearing a jacket for at leastthree days prior to dose administration. Additionally, the animals werealso acclimated to wearing an Elizabethan collar (e-collar) during thejacket acclimation.

Surgical Procedure and Dosing Procedure

Animals were catheterized the day prior to dose administration. Apercutaneous catheter was placed (using aseptic technique and sterilebandaging) in the cephalic vein distal to the elbow. The animals werefree-moving in their cages during continuous infusion doseadministration. To facilitate continuous infusion dose administration,the peripheral catheter was attached to an extension set routedunderneath a canine jacket and then attached to a tether infusionsystem. To prevent the animals from accessing/removing the peripherallyplaced percutaneous catheter, the catheterization site was bandagedusing Vet Wrap and an e-collar was placed on the animals for theduration of the treatment (i.e., the catheterized period). During thepretreatment period, the venous catheter was infused continuously at arate of approximately 2-4 mL/hr with 0.9% sodium chloride for injection,USP (saline) to maintain catheter patency. Prior to dosing, the infusionsystem was pre-filled (slow bolus infusion) with the respective dosingsolution to ensure that dosing began as soon as the infusion pump wasstarted. The infusion line was connected to a reservoir containing thecontrol or test compound and the infusion was started. Test compositionswere infused continuously, at a predetermined constant infusion rate (1or 2 mL/kg/hr), for 24 hours and were compared at molar equivalent doserates.

Clinical Observations, Clinical Pathology, and Microscopic Pathology

A detailed clinical examination of each animal was performed twice dailyand body temperature measurements and blood samples for clinicalpathology were collected from all animals pre-dose and 6 hours, 12hours, 24 hours and 72 hours post start of composition infusion. At thetermination of the study, all animals were euthanized at their schedulednecropsy and complete necropsy examinations were performed. Selectedtissues were collected, fixed and stored for potential futuremicroscopic examination. The cephalic vein containing the infusioncatheter was dissected intact along with the brachial vein and examinedalong its entire length. The location of the catheter tip was marked onthe unfixed specimen. After fixation, the specimen was trimmed andprocessed to slide to provide transverse histologic sectionsrepresenting the catheter tip and surrounding tissues both proximal anddistal to the catheter tip (i.e., 1 cm distal to the catheter tip, atthe catheter tip, and 1, 5, 10, 15, and 20 cm proximal to the cathetertip). Relative to the catheter tip, “proximal” was defined as closer tothe heart and “distal” was defined as further from the heart.

Safety Assessment

Clinical pathology changes consistent with an inflammatory syndrome wereobserved at some dose rates of compounds of formulas (1), (2) (83),(84), (85), (86) and CXL-1020. Each compound was formulated withCAPTISOL® (7% w/v) in sterile water at a pH of 4. The most sensitivebiomarkers of the inflammation were: (1) white cell count (WBC, obtainedas (number of white blood cells)/μL by multiplying the values in therightmost portion of FIG. 2 by 103), (2) fibrinogen concentration (givenin mg/dL in the rightmost portion of FIG. 2), and (3)C-Reactive Protein(CRP) concentration (given in mg/L in the rightmost portion of FIG. 2).The severity of the changes was dependent on the identity of thecompound and the dose rate at which the compound was administered (FIG.2). In FIG. 2, a score ranging from 0 (low severity) to 2 (highseverity) was assigned to each of these biomarkers of inflammationaccording to the rightmost portion in that figure. A cumulative scorewas calculated from the sum of these marker scores. The NOAELs,determined based on these clinical pathology markers and expressed inmolar equivalent dose rates (μg/kg/min) to CXL-1020, are provided inTable 7.

TABLE 7 No Observed Adverse Effect Levels (NOAEL) of Nitroxyl DonorsNOAEL (μg/kg/min) Compound (actual)N-Hydroxy-2-methanesulfonylbenzene-1-sulfonamide <0.03 (CXL-1020)N-Hydroxy-5-methylfuran-2-sulfonamide (1) >20N-Hydroxy-3-methanesulfonylbenzene-1-sulfonamide (2) 3N-Hydroxyfuran-2-sulfonamide (83) 3N-Hydroxy-5-methylthiophene-2-sulfonamide (84) 10N-Hydroxy-1-methyl-1H-pyrazole-3-sulfonamide (85) 35-Chloro-N-hydroxythiophene-2-sulfonamide (86) 3

For CXL-1020, significant elevations in WBC, fibrinogen and CRP wereobserved, even at concentrations as low as 0.03 μg/kg/min. The longerhalf-life compounds of formulas of formulas (1), (2) (83), (84), (85)and (86) all have a NOAEL at doses significantly higher than that ofCXL-1020. The compound of formula (1) has the most favorabletoxicological profile, showing no adverse effects at doses at least ashigh as 20 μg/kg/min. This represents a greater than 660-foldimprovement of the compound of formula (1) relative to CXL-1020.

Collectively, these findings suggest that CXL-1020 infusion causes aninflammatory syndrome, which is substantially reduced with the longerhalf-life nitroxyl donors of the disclosure.

The findings suggested that the vascular toxicity associated withCXL-1020 at the catheter tip, downstream of the catheter tip and incertain circumstances, upstream of the catheter tip, were due to localinflammation caused by nitroxyl release. Moreover, it was postulatedthat inflammation can be significantly mitigated at these sites usinglonger half-life nitroxyl donors. Confirmation of this was obtainedthrough evaluating the nitroxyl donors through detailed histopathologyof the vasculature at the site of insertion of into the femoral vein (15cm distal to the catheter tip), along the catheter track to the cathetertip, and past the tip downstream 20 cm. Microscopic pathology findingsof edema, hemorrhage, vascular inflammation and perivascularinflammation were determined at particular dose rates of the nitroxyldonors.

FIG. 3 depicts a “heat-map” showing a composite score of the microscopicpathology findings in which the severity of vascular inflammation,hemorrhage, thrombus and vascular degeneration/regeneration was scoredin sections of the vasculature as described above. Findings of (1)edema, (2) vascular and perivascular inflammation, and (3) hemorrhagewere scored (each assigned a value selected from: 0=within normallimits; 1=minimal; 2=mild; 3=moderate; 4=severe) in sections of thevessel beginning 1 cm distal (upstream) from the catheter tipprogressing 20 cm proximal (downstream) from the catheter tip. Acomposite score was calculated from the sum of these findings scores. InFIG. 3, the cumulative histology composite score ranges from 0-2 (lowseverity) to 11-12 (high severity). The severity of the microscopicchanges and the distance from the catheter tip in which they weredetected was observed to be dependent on the identity of the nitroxyldonor and the dose rate at which the nitroxyl donor was administered.The NOAEL values determined based on these microscopic pathology markersfor a series of nitroxyl donors, expressed in molar equivalent doserates (μg/kg/min) to CXL-1020, are provided in Table 8.

TABLE 8 No Observed Adverse Effect Levels (NOAEL) of Nitroxyl DonorsNOAEL (μg/kg/min) (molar equivalent Compound to CXL-1020)N-Hydroxy-2-methanesulfonylbenzene-1-sulfonamide <3 (CXL-1020)N-Hydroxy-5-methylfuran-2-sulfonamide (1) ≧180N-Hydroxy-3-methanesulfonylbenzene-1-sulfonamide (2) ≧180N-Hydroxyfuran-2-sulfonamide (83) ≧90N-Hydroxy-5-methylthiophene-2-sulfonamide (84) ≧60N-Hydroxy-1-methyl-1H-pyrazole-3-sulfonamide (85) ≧1805-Chloro-N-hydroxythiophene-2-sulfonamide (86) ≧180

The findings presented in Table 8 that the longer half-life nitroxyldonors (e.g., compounds of formulas (83), (84), (85) and (86)) have asubstantially improved toxicological profile relative to CXL-1020. Theside effect profile at any dose decreased in severity as a function ofdistance from the catheter tip, and the severity of vascular sideeffects decreased with decreasing dose. These findings confirmed a largesafety margin for compounds of formulas compounds of formulas (83),(84), (85) and (86), which can translate into a substantially improvedtherapeutic index in humans, and suitability for intravenousadministration at therapeutically effective doses and dosage rates.

5.5 Example 6 Increasing pH Improves Toxicological Profile

Three nitroxyl donors (CXL-1020, compound (2), and compound (86)) wereformulated at a pH of 4 and at a pH of 6 (in a potassium acetate buffer)and the toxicological profiles of the compositions were assessed. Forsamples at a pH of 4, the compositions were prepared by admixing a 1:1molar ratio of the nitroxyl donor:CAPTISOL®, lyophilizing the admixture,then diluting the lyophilized admixture into D5W. For samples at a pH of6, the compositions were prepared by admixing a 1:1 molar ratio of thenitroxyl donor:CAPTISOL®, lyophilizing the admixture, then diluting thelyophilized admixture into D5W with 5 mM potassium phosphate. Compoundswere infused at a rate of 3 μg/kg/min. As shown in FIG. 4, increasingthe infusate pH from approximately 4 to approximately 6 improved thetoxicology of the three compounds.

5.6 Concentrate Stability Assessment 5.6.1 Example 7 Compound of Formula(1)

The stability of liquid concentrates of the compound of formula (1) andCAPTISOL® was evaluated. Three concentrations of the compound of formula(1) were assessed: 21.2 mg/mL, 50 mg/mL and 100 mg/mL. Samples wereprepared to the three target concentrations in four aqueous vehiclescomprising different percentages of CAPTISOL®, as summarized in Table 9.The appropriate amounts of solid and vehicle were combined, and uponcomplete dissolution, the pH of each sample was adjusted to 4.0 byadding 1 N NaOH. The samples were prepared on a 1.5-mL scale. Aliquotswere stored at 2° C.-8° C. and 25° C.

TABLE 9 Samples Prepared for Assessment of the Compound of Formula (1)Concentrate Stability Compound of Formula (1) % Concentration CAPTISOL ®Sample # (mg/mL) (w/v) C1 21.2 0 C2 30 C3 50 0 C4 10 C5 20 C6 30 C7 1000 C8 10 C9 20 C10 30

Upon preparation and after 1, 3, and 7 days of storage, samples wereremoved from their respective temperature conditions and their visualappearances noted. Samples were analyzed by HPLC (XBridge Phenyl Column(Waters); UV absorbance detector at 272 nm; mobile phase a step gradientof aqueous acetonitrile containing 0.1% (v/v) formic acid), and the pHof each sample was measured. The results are summarized in Table 10 andTable 11. The recovery values are normalized to the concentrationsobserved right after preparation of the concentrate (t=0). Completerecovery (within the accuracy of the method) was achieved in all samplesstored at 2° C.-8° C. over the 7 days but not in all samples stored at25° C.

Correspondingly, the decrease in pH and increase in intensity of yellowcolor were less pronounced in the refrigerated samples than in thesamples stored at a temperature of 25° C. Complete recovery was observedafter 7 days in the 21.2 and 50 mg/mL samples prepared in 30% CAPTISOL®and after 3 days in the 100 mg/mL sample prepared in the same vehicle.Recovery of greater than 90% was also observed after three days in the50 mg/mL sample prepared in 20% CAPTISOL®. The stability was greatest atlower concentrations, higher percentages of CAPTISOL®, and lowertemperature.

TABLE 10 Visual Appearance of Concentrate Stability Samples Compound of% Formula (1) Storage CAPTISOL ® Concentration Temperature VisualAppearance Sample # (w/v) (mg/mL) (° C.) t = 0 t = 1 d t = 3 d t = 7 dC1 0 21.2 2-8 A A A A 25 A B C C2 30 21.2 2-8 A A A A 25 A A A C3 0 502-8 B B B B 25 B C D C4 10 50 2-8 B B B B 25 B C D C5 20 50 2-8 B B B B25 B B C C6 30 50 2-8 B B B B 25 B B B C7 0 100 2-8 B B B B 25 C D D C810 100 2-8 B B B B 25 C D D C9 20 100 2-8 B B B B 25 C D D C10 30 1002-8 B B B B 25 C C C A = clear, colorless B = clear, very pale yellow C= clear, pale yellow D = clear, yellow

TABLE 11 Results of Analysis of Concentrate Stability SamplesConcentration % Compound of Storage CAPTISOL ® Formula (1) Temp.Recovery from t0, % pH Sample # (w/v) (mg/mL) (° C.) t = 1 d t = 3 d t =7 d t = 0 t = 1 d t = 3 d t = 7 d C1 0 21.2 2-8 101% 100% 99% 4.03 3.413.03 2.81 25 103% 82% 38% 3.50 1.73 1.29 C2 30 21.2 2-8 99% 101% 98%4.02 3.93 3.82 3.72 25 100% 101% 98% 3.65 3.44 3.23 C3 0 50 2-8 100% 99%99% 4.02 3.38 3.25 3.00 25 100% 79% 50% 2.93 1.38 1.13 C4 10 50 2-8 98%96% 97% 4.00 3.35 3.29 3.22 25 99% 82% 55% 3.03 1.66 1.29 C5 20 50 2-899% 97% 97% 4.00 3.14 3.13 3.04 25 100% 92% 69% 2.87 2.05 1.42 C6 30 502-8 100% 100% 98% 3.98 3.61 3.61 3.40 25 100% 101% 98% 3.21 2.95 2.84 C70 100 2-8 100% 97% 98% 3.96 2.96 2.86 2.75 25 98% 70% 68% 2.13 1.14 1.07C8 10 100 2-8 101% 100% 99% 4.02 2.51 2.41 2.18 25 91% 78% 71% 1.67 1.211.12 C9 20 100 2-8 99% 99% 99% 3.96 3.30 3.20 3.03 25 100% 84% 70% 2.571.42 1.14 C10 30 100 2-8 102% 102% 102% 3.99 3.39 3.27 3.11 25 103% 101%80% 2.90 2.20 1.31

5.6.2 Example 8 Compound of Formula (2)

The storage stability of a liquid concentrate of the Compound of formula(2) (30 mg/mL) in the vehicle 30% CAPTISOL® (w/v) at pH 4.0, wasassessed at 4° C. and 25° C. over 7 days, with time points after 1, 3and 7 days. At each time point samples were assessed for visualappearance, pH, and concentration and purity by HPLC (XBridge PhenylColumn (Waters); UV absorbance detector at 272 nm; mobile phase a stepgradient of aqueous acetonitrile containing 0.1% (v/v) formic acid).

The selected vehicle, CAPTISOL® (30% w/v) in water with pH adjusted to4.0, was prepared by accurately weighing 30 grams of CAPTISOL® into a150 mL beaker and dissolved with 45 mL of water. The pH was adjusted topH 4.0 by addition of 0.1N HCl. Subsequently, the vehicle wastransferred to a volumetric flask and brought to 100 mL final volume byaddition of water. After incubation at a temperature of about 25° C. for30 minutes, the pH of the vehicle was re-adjusted to pH 4.0 by additionof 0.1N HCl. The vehicle formed a clear, colorless solution.

A concentrated solution of the compound of formula (2) was prepared asfollows. A stir bar and 30 mL of vehicle were added to a 150 mL beaker.Approximately 1.8 g of the compound of formula (2) was dispensed andtransferred to the beaker under low to medium stirring. After 45 minutesof stirring at a temperature of about 25° C. (protected from light), theconcentrate formed a clear, colorless solution with some small, whiteclumps of the compound of formula (2) floating in solution. Theremaining clumps were gently broken-up using a spatula. Following anadditional 45 minutes of stirring, the concentrate formed a clear,colorless solution without any visible solids. The concentrate was thenfiltered (0.2 μm) through a 0.22 μm PVDF syringe filter.

For t=0 h testing, aliquots were distributed into vials and analyzed byHPLC (XBridge Phenyl Column (Waters); UV absorbance detector at 272 nm;mobile phase a step gradient of aqueous acetonitrile containing 0.1%(v/v) formic acid) and the sample pH was determined. Twelve aliquots of1 mL of the concentrate were distributed into microcentrifuge tubes forstorage at 4° C. and 25° C. After approximately 24, 72 and 168 hours ofstorage, two aliquots were removed from each storage condition andassessed for visual appearance, pH, and concentration and purity byHPLC. All samples were clear, colorless solutions. The pH of the samplesstored at 4° C. and 25° C. decreased from 3.7 to 3.6 and 3.3,respectively, over the 7 days. Both vehicles sustained the compound offormula (2) at a concentration of 30 mg/mL over 7 days, as summarized inTable 12. In Table 12, the term “c/c” refers to clear and colorless. Nodetectable levels of the known degradant (compound of formula (101))were observed.

TABLE 12 Summary of Observed Properties of a Concentrate Solution of theCompound of Formula (2) During Storage Over 7 Days Storage Time PointCondition Parameter Sample 0 h 24 h 72 h 168 h  4° C. Concentration,mg/mL 1 30.3 30.6 29.6 29.7 2 30.2 29.4 29.9 pH 1 3.71 3.70 3.66 3.58 23.70 3.66 3.61 Appearance 1 c/c c/c c/c c/c 2 c/c c/c c/c ObservedDegradant 1 No No No No Compound of 2 No No No Formula (101), mg/mL 25°C. Concentration, mg/mL 1 30.3 30.2 29.4 29.5 2 30.2 29.8 29.4 pH 1 3.713.47 3.34 3.32 2 3.48 3.34 3.30 Appearance 1 c/c c/c c/c c/c 2 c/c c/cc/c Observed Degradant, 1 No No No No Compound of 2 No No No Formula(101), mg/mL

5.7 Stability of Intravenous Dosing Solutions 5.7.1 Example 9 Compoundof Formula (1)—Dosing Solution Stored at 25° C.

The stability of dosing solutions of the compound of formula (1)prepared from a CAPTISOL® concentrate diluted intocommercially-available IV diluents was assessed at 25° C. over 48 hours,with analysis points at 0, 8, 12, 16, 24, and 48 hours after dilution.Due to the analysis points required, two studies were executed withseparate sets of dosing solutions. The first (group A) encompassed alltime points except that at 16 hours. The second (group B) entailedanalysis at 0 and 16 hours only. The concentrates used to prepare thetwo sets of dosing solutions were prepared from two separate vials ofthe same lot of lyophilized drug product (24 mg/mL Compound of formula(1)/30% CAPTISOL®).

Concentrate Preparation

One vial of lyophilized drug product (24 mg/mL Compound of formula(1)/30% CAPTISOL®, pH 4) was reconstituted with 10 mL of water forinjection quality water (WFI) to prepare each concentrate (for dosingsolution groups A and B). The pH values of the resultant solutions weremeasured, and were determined to be approximately 3.9 for both vials. NopH adjustment was performed. The concentrates were diluted and analyzedby HPLC (XBridge Phenyl Column (Waters); UV absorbance detector at 272nm; mobile phase a step gradient of aqueous acetonitrile containing 0.1%(v/v) formic acid), and both were determined to contain 20-21 mg/mL ofthe compound of formula (1), rather than the nominal value of 24 mg/mL,ostensibly due to contribution of the dissolved API and CAPTISOL® to thetotal solution volume.

Diluent Preparation

Commercially-available potassium acetate and potassium phosphatesolutions were selected for evaluation. Potassium acetate was obtainedcommercially, and a USP potassium phosphate solution was preparedaccording to the Hospira product insert for the commercial product. Eachsolution was diluted to 10 mM in 5% dextrose (D5W) and 2.5% dextrose(D2.5W). Commercially-available D5W was diluted 2-fold with WFI qualitywater to produce the D2.5W solution. The pH of each concentrated anddiluted solution was measured; the results are presented in Table 13.

TABLE 13 Results of pH Measurement of Selected Diluents DiluentConcentration pH Acetate 10 mM in D2.5W 6.2 10 mM in D5W 6.0 Initial(2M) 6.7 Phosphate 10 mM in D2.5W 6.8 10 mM in D5W 6.7 Initial (3M) 6.5

Dosing Solution Preparation

The compound of formula (1) concentrate was diluted volumetrically on a5 mL scale into the 10 mM diluent solutions to achieve concentrations of8, 1, and 0.1 mg/mL of the compound of formula (1), as summarized inTable 14. Each sample was prepared in duplicate. The dextrose content inthe 10% CAPTISOL® solution was reduced to ensure that the dosingsolutions were substantially isotonic. Each solution was stored at 25°C.

TABLE 14 Preparation of Dosing Solutions for Stability EvaluationCompound of Formula (1) Dilution CAPTISOL ® (mg/mL) Diluent factor (%w/v) 8.0 10 mM acetate or 3  10% phosphate in D2.5W 1.0 10 mM acetate or24 1.3% 0.1 phosphate in D5W 240 0.1%

Sample Analysis

Samples were analyzed upon preparation and after 8, 12, 16, 24, and 48hours of storage at 25° C. The visual appearance of each sample wasnoted, the pH was measured, and each sample was analyzed by HPLC forconcentration and presence of the major degradant, the compound offormula (100).

Results

The results of the stability evaluation are presented in Table 15, Table16, and Table 17. In Table 17, the presence of a peak corresponding tothe degradant (the compound of formula (100)) in a sample is denoted byan “×”.

The results were generally consistent for each duplicate within a pairand between corresponding dosing solutions prepared in groups A and B. Adifference in recovery was observed between duplicates at the 24 and 48hour time points for the samples prepared to contain 0.1 mg/mL of thecompound of formula (1) in phosphate.

Complete recovery (within the accuracy of the HPLC method) and absenceof a detectable degradant (compound of formula (100)) peak wasmaintained over 48 hours for the samples prepared to 8 mg/mL of thecompound of formula (1) in acetate- and phosphate-based diluents. Thesesamples actually contained approximately 7 mg/mL of the compound offormula (1), consistent with the concentration of 20-21 mg/mL compoundof formula (1) in the concentrate. In both diluents, stability wassuperior in the samples prepared to 8 mg/mL compound of formula (1) thanin the samples prepared to lower concentrations. Without being bound bytheory, the better stability of these samples compared to those preparedto lower concentrations of the compound of formula (1) might beattributed to the higher CAPTISOL® concentration (10% in the dilutedsolutions).

All samples remained clear and colorless over the 48 hours of storage.The pH of all samples decreased over time. The known degradant (compoundof formula (100)) was observed upon preparation (at t0) in all samplesprepared to contain 0.1 mg/mL of the compound of formula (1) and at allsubsequent time points in all samples prepared to contain 0.1 mg/mL and1 mg/mL of the compound of formula (1).

In general, stability decreased with decreasing concentration of thecompound of formula (1). Without being bound by theory, the decreasedstability was likely due to the lower percent CAPTISOL® in the dosingsolutions. The initial extent of degradation (through 16 hours) wassimilar in the samples prepared to contain 0.1 mg/mL of the compound offormula (1) in the acetate- and phosphate-based diluents. However, thestability of the samples prepared to contain 1 mg/mL demonstratedsignificantly better stability in acetate than in phosphate.

TABLE 15 Results of Dosing Solution Stability Evaluation at 25° C.,Percent Recovery Compound of Formula (1) Compound of mg/mL Recovery fromt0 Dosing Formula (1) t0 t0 8 h 12 h 16 h 24 h 48 h Solution DuplicateDiluent mg/mL (group A) (group

(A) (A) (B) (A) (A) 1 a 10 mM acetate 8.0 6.94 7.06 101% 102% 101% 102%101% b in D2.5W 6.95 7.06 101% 102% 101% 102% 103% 2 a 10 mM acetate 1.00.86 0.85 97% 97% 97% 94% 92% b in D5W 0.87 0.84 98% 98% 98% 96% 95% 3 a10 mM acetate 0.1 0.10 0.09 81% 78% 66% 67% 55% b in D5W 0.10 0.09 80%75% 68% 63% 51% 4 a 10 mM phosphate 8.0 6.98 6.79 98% 99% 102% 99% 100%b in D2.5W 7.00 6.93 99% 94% 100% 100% 100% 5 a 10 mM phosphate 1.0 0.870.85 89% 86% 86% 78% 71% b in D5W 0.88 0.85 90% 83% 82% 79% 72% 6 a 10mM phosphate 0.1 0.10 0.10 83% 78% 72% 62% 41% b in D5W 0.10 0.10 79%72% 68% 50% 32%

indicates data missing or illegible when filed

TABLE 16 Results of Dosing Solution Stability Evaluation at 25° C., pHCompound of pH Dosing Formula (1) t0 t0 8 h 12 h 16 h 24 h 48 h SolutionDuplicate Diluent mg/mL (group A) (group B) (A) (A) (B) (A) (A) 1 a 10mM acetate 8.0 5.6 5.5 5.4 5.4 5.4 5.4 5.3 b in D2.5W 5.6 5.5 5.5 5.45.4 5.3 5.3 2 a 10 mM acetate 1.0 5.7 5.7 5.6 5.7 5.5 5.5 5.3 b in D5W5.9 5.7 5.7 5.8 5.5 5.5 5.4 3 a 10 mM acetate 0.1 6.1 5.9 5.9 5.9 5.45.7 5.7 b in D5W 5.8 5.9 5.9 5.9 5.3 5.7 5.5 4 a 10 mM 8.0 6.3 6.1 5.95.9 5.6 5.5 5.0 b phosphate 6.3 6.2 5.9 5.8 5.6 5.5 4.7 in D2.5W 5 a 10mM 1.0 6.5 6.6 6.3 6.4 6.2 6.1 5.8 b phosphate 6.6 6.5 6.3 6.4 6.1 6.36.0 in D5W 6 a 10 mM 0.1 6.8 6.7 6.6 6.6 6.3 6.5 6.4 b phosphate 6.8 6.86.5 6.5 6.2 6.5 6.4 in D5W

TABLE 17 Results of Dosing Solution Stability Evaluation at 25° C. -Measuring Appearance of Compound of Formula (100) Compound of Compoundof Formula (100) Dosing Formula (1) t0 t0 8 h 12 h 16 h 24 h 48 hSolution Duplicate Diluent mg/mL (group A) (group B) (A) (A) (B) (A) (A)1 a 10 mM 8.0 b acetate in D2.5W 2 a 10 mM 1.0 X X X X X b acetate X X XX X in D5W 3 a 10 mM 0.1 X X X X X X X b acetate X X X X X X X in D5W 4a 10 mM 8.0 b phosphate in D2.5W 5 a 10 mM 1.0 X X X X X b phosphate X XX X X in D5W 6 a 10 mM 0.1 X X X X X X X b phosphate X X X X X X X inD5W

5.7.2 Example 10 Compound of Formula (1)—Dosing Solution Stored at 2°C.-8° C. Followed by Storage at 25° C.

The stability of dosing solutions of the compound of formula (1)prepared from a CAPTISOL® concentrate diluted into commerciallyavailable IV diluents was prepared as described in Example 9. Thesolutions were assessed at 2° C.-8° C. over 24 hours followed by storageat 25° C. over 48 hours. As shown in Table 18, recoveries of thecompound of formula (1) were generally higher than for the correspondingsamples stored at 25° C. for all dosing solutions (see Table 16 fromprevious example), suggesting improved stability for dosing solutionsprepared and stored at 2° C.-8° C. prior to storage at a temperature of25° C.

TABLE 18 Results of Dosing Solution Stability Evaluation at 2° C.-8° C.and 25° C., Percent Recovery Compound of Formula (1) Recovery from t0mg/mL 32 h 36 h 40 h 48 h 72 h Compound of t0 t0 24 h 24 h (A) (A) (B)(A) (A) Formula (1) (group

(group B) (A) (B) 8 h at 12 h at 16 h at 24 h at 48 h at Sample #Diluent mg/mL 2-8° C. 2-8° C. 2-8° C. 2-8° C. 25° C. 25° C. 25° C. 25°C. 25° C. 1 10 mM acetate 8.0 7.13 6.91 99% 103% 101% 99% 103% 97% 99%in D2.5W 2 10 mM acetate 1.0 0.89 0.89 99% 100% 98% 98% 93% 95% 92% inD5W 3 10 mM acetate 0.1 0.10 0.10 97% 97% 92% 89% 67% 82% 73% in D5W 410 mM 8.0 7.18 7.08 100% 102% 99% 99% 100% 97% 97% phosphate in D2.5W 510 mM 1.0 0.89 0.88 99% 101% 95% 93% 90% 87% 81% phosphate in D5W 6 10mM 0.1 0.11 0.10 97% 97% 89% 86% 76% 76% 63% phosphate in D5W

indicates data missing or illegible when filed

5.7.3 Example 11 Compound of Formula (2)—Dosing Solution Stored at 25°C.

A series of dosing solutions of the compound of formula (2) for IVadministration was assessed. The selected concentrate of compound offormula (2), prepared at 30 mg/mL in a vehicle of 30% CAPTISOL® at pH4.0, was evaluated at low, mid, and high concentrations (0.1, 1 and 5mg/mL, respectively) upon dilution into various dosing solutions. Fordilution of the compound of formula (2) to 0.1 and 1 mg/mL, three dosingsolutions were evaluated; 1) D5W, 2) D5W with 5 mM K-phosphate (pH=6),and 3) D5W with 20 mM K-phosphate (pH=6). To maintain iso-osmolality fordilutions of the compound of formula (2) to 5 mg/mL, the concentrationof dextrose in the dosing solutions was reduced to 2.5% (w/v). Thus, thedosing solutions evaluated were; (1) D2.5W, (2) D2.5W with 5 mMK-phosphate (pH=6), and (3) D2.5W with 20 mM K-phosphate (pH=6).

The potential dosing solutions were assessed for visual appearance, pH,osmolality, and concentration and purity by HPLC (XBridge Phenyl Column(Waters); UV absorbance detector at 272 nm; mobile phase a step gradientof aqueous acetonitrile containing 0.1% (v/v) formic acid) afterapproximately 0, 16, 24, and 48 hours of storage at 25° C. All sampleswere clear, colorless solutions -with the sole exception of 5 mg/mL ofthe compound of formula (2) in D2.5W with 5 mM phosphate which had aclear, light yellow appearance after 48 hours at 25° C. All solutionswere iso-osmotic (290+/−50 mOsm/kg)—with the sole exception of 1 mg/mLof the compound of formula (2) in D5W with 20 mM phosphate which had anosmolality of approximately 350 mOsm/kg. Furthermore, with the exceptionof 5 mg/mL of the compound of formula (2) in D2.5W with 5 mM phosphate,all other dosing solutions sustained the compound of formula (2) at thetarget concentrations of 0.1, 1 and 5 mg/mL over 48 hours. In addition,the known degradant, the compound of formula (101), formed by release ofthe active HNO group, was observed after 16 hours at 25° C. in smallquantities by HPLC in the dosing solutions containing phosphate buffer.The observed amount of the compound of formula (101) was on the order ofthe limit of detection of the method.

The stability of 5 mg/mL of the compound of formula (2) dosing solutionswas further evaluated as a function of pH and buffer. A concentratedsolution of the compound of formula (2), prepared at 30 mg/mL in avehicle of 30% CAPTISOL® at pH 4.0, was diluted to 5 mg/mL into fourpotential dosing solutions. The four dosing solutions were evaluated: 1)D2.5W, 5 mM K-phosphate (pH=6.0), 2) D2.5W with 5 mM K-citrate (pH=6.0),3) D2.5W, 5 mM K-citrate (pH=5.0), and 4) D2.5W, 5 mM K-acetate(pH=5.0). All dosing solutions of the compound of formula (2) wereiso-osmotic (290+/−50 mOsm/kg). After approximately 24 and 48 hours ofstorage at 25° C., the dosing solutions were assessed for visualappearance, pH, and concentration and purity by HPLC. The non-phosphatedosing solutions were clear, colorless and sustained the compound offormula (2) at the target concentration of 5 mg/mL over 48 hours; whileconsistent with the dosing solution screen, the 5 mg/mL compound offormula (2) in D2.5W with 5 mM phosphate (pH 6.0) dosing solution wasclear, light yellow in appearance with only 60% recovery of the compoundof formula (2) after 48 hours. Furthermore, the known degradant, thecompound of formula (101), was observed in small quantities by HPLC inall samples except 5 mg/mL of the compound of formula (2) in D2.5W, 5 mMcitrate (pH 5.0).

After 7 days of storage at 25° C. the non-phosphate dosing solutionswere still clear and colorless in appearance. The smallest increase inacidity over the 7 days was measured for the 5 mg/mL of the compound offormula (2) in D2.5W, 5 mM citrate pH 6.0 dosing solution, while theD2.5W, 5 mM citrate pH 5.0 dosing solution had the smallest change in pHover the initial 24-48 h. Furthermore, after 14 days of storage at 25°C. the samples with dosing solution containing 5 mM citrate pH 6.0 werestill clear, colorless solutions, while the dosing solutions containingeither 5 mM citrate or 5 mM acetate at pH 5.0 were clear, yellowsolutions. The results are summarized in Table 19.

TABLE 19 Recovery of the Compound of Formula (2) from 5 mg/mL DosingSolutions Time Point Dosing Solution Sample 0 h 24 h 48 h (1). D2.5W, 5mM 1  101%  100% 60.7% phosphate, pH 6.0 2  100%  100% 62.8% (2). D2.5W,5 mM 1  101% 98.6% 96.7% citrate, pH 6.0 2  101% 98.8% 96.5% (3). D2.5W,5 mM 1  101%  100% 99.1% citrate, pH 5.0 2  100%  102% 99.3% (4). D2.5W,5 mM 1 95.6% 95.4% 95.4% acetate, pH 5.0 2 96.0% 96.8% 94.8%

5.8 Example 12 Evaluation of CAPTISOL®/Nitroxyl Donor Ratios

The compound of formula (1) was chosen as a model nitroxyl donor. Astability assessment was performed with concentrate solutions containingmolar ratios of CAPTISOL® (MW 2163 g/mol) to the compound of formula (1)(MW 177.18 g/mol) selected based on projected toxicology studies. Theconcentrates evaluated are summarized in Table 20. Concentrate sampleswere prepared by combining the appropriate amounts of solid and vehicle,and upon complete dissolution, the pH of each sample was adjusted to 4.0by adding 1 N NaOH. The samples were prepared on a 1.8-mL scale.Aliquots of each solution were stored at 25° C.

TABLE 20 Summary of Concentrate Samples Evaluated Molar Ratio, %Compound of CAPTISOL ®: Sample CAPTISOL ® Formula (1), Target Compoundof # (w/v) mg/mL pH Formula (1) C11 10% 40 4.0 0.20 C12 20% 40 4.0 0.41C13 30% 40 4.0 0.61

Each concentrate solution was additionally diluted into IV diluents tothe highest and lowest concentrations expected to be administered duringtoxicology studies (8 mg/mL and 0.02 mg/mL of the compound of formula(1), respectively). The dosing solutions evaluated are summarized inTable 21. The vehicles were selected to produce administrableformulations approximately isoosmotic with human blood (about 290mOsm/kg water). The dilutions were performed volumetrically, on a 5-mLscale for the higher concentration samples and on a 25-mL scale for thelower concentration samples. Aliquots of each solution were stored at25° C.

TABLE 21 Summary of Dosing Solutions Evaluated Compound of Final %Sample Concentrate Formula (1), Dilution CAPTISOL ® # # Vehicle mg/mLFactor (about w/v) D7 C11 D5W 8 5    2% D8 C12 D5W 8 5    4% D9 C13D2.5W 8 5    6% D10 C11 D5W 0.02 2000 .005% D11 C12 D5W 0.02 2000 .010%D12 C13 D5W 0.02 2000 .015%

Upon preparation (t0) and after 1 day (24 hours) and 2 days (48 hours)of storage, samples were removed from storage and their visualappearances noted. All concentrate samples remained clear and paleyellow over the 48 hours. Dosing solutions D7-D9 were clear and verypale at each time point and dosing solutions D10-D12 remained clear andcolorless. At each time point, samples were analyzed by HPLC (XBridgePhenyl Column (Waters); UV absorbance detector at 272 nm; mobile phase astep gradient of aqueous acetonitrile containing 0.1% (v/v) formicacid). The results of the HPLC analysis of the concentrates aresummarized in Table 22. The results of the HPLC analysis of the dosingsolutions are summarized in Table 23. Complete recovery (within theaccuracy of the method) was achieved over 48 hours in all concentratesand dosing solutions. The major degradation product of the compound offormula (1) (i.e., the compound of formula (100)) was observed at lowconcentrations in the dosing solutions prepared to 0.02 mg/mL. Thedegradant concentration did not increase over time and did not affectrecovery of the compound of formula (1).

TABLE 22 Results of HPLC Analysis of Concentrate Samples Compound ofRecovery Sample % CAPTISOL ® formula (1), mg/mL from t0, % # (w/v) t = 0t = 1 d t = 2 d t = 1 d t = 2 d C11 10 39.4 39.9 38.2 101% 97% C12 2040.9 39.9 40.6 97% 99% C13 30 40.6 40.2 40.1 99% 99%

TABLE 23 Results of HPLC Analysis of Dosing Solutions Concentration ofCompound Compound of Recovery of Formula (1) Formula (1), mg/mL from t0,% Sample # Concentrate # mg/mL t = 0 t = 1 d t = 2 d t = 1 d t = 2 d D7C11 8.00 7.96 8.07 7.99 101% 100% D8 C12 8.00 8.06 8.06 7.85 100% 97% D9C13 8.00 8.20 8.17 8.06 100% 98% D10 C11 0.02 0.018 0.019 0.019 106%105% D11 C12 0.02 0.020 0.020 0.020 100% 100% D12 C13 0.02 0.019 0.0210.020 108% 105%

5.9 Synthesis of Compounds

The compounds disclosed herein can be made according to the methodsdisclosed below or by procedures known in the art. Starting materialsfor the reactions can be commercially available or can be prepared byknown procedures or obvious modifications thereof. For example, some ofthe starting materials are available from commercial suppliers such asSigma-Aldrich (St. Louis, Mo.). Others can be prepared by procedures orobvious modifications thereof disclosed in standard reference texts suchas March's Advanced Organic Chemistry (John Wiley and Sons) and Larock'sComprehensive Organic Transformations (VCH Publishers).

Example 13 Preparation of N-Hydroxy-5-methylfuran-2-sulfonamide (1)

To a solution of hydroxylamine (0.92 mL of a 50% aqueous solution; 13.8mmol) in THF (6 mL) and water (2 mL) cooled to 0° C. was added5-methylfuran-2-sulfonyl chloride (1 g, 5.5 mmol) as a solution in THF(6 mL) dropwise so as to maintain the temperature below 10° C. Thereaction was stirred for 5 minutes, after which time TLC (1:1hexane:ethyl acetate (H:EA)) showed substantially complete consumptionof the sulfonyl chloride. The reaction was diluted twice with 50 mLdichloromethane (DCM) and the organic portion was separated and washedwith water (10 mL). The organic portion was dried over sodium sulfate,filtered and concentrated under reduced pressure. The product waschromatographed with a silica gel column eluting with heptanes:EtOAcfollowed by trituration with heptane to provide the title compound as ayellow solid (0.59 g, 61% yield). LC-MS t_(R)=0.91 min; ¹H NMR (DMSO,500 MHz) δ ppm 9.82 (1H, d, J=3.1 Hz), 9.64 (1H, d, J=3.2 Hz), 7.10 (1H,d, J=3.4 Hz), 6.36 (1H, d, J=3.4 Hz), 2.36 (3H, s).

Example 14 Preparation ofN-Hydroxy-3-methanesulfonylbenzene-1-sulfonamide (2)3-Methanesulfonylbenzene-1-sulfonyl chloride

The intermediate 3-methanesulfonylbenzene-1-sulfonyl chloride wassynthesized according to the methods disclosed in Park et al., J. Med.Chem. 51(21):6902-6915 (2008). Specifically, methyl sulfonyl benzene(110 g, 0.7 mol) was heated for 18 hours at 90° C. in chlorosulfonicacid (450 mL, 6.7 mol) after which time the reaction mixture was allowedto cool to a temperature of about 21° C. before slowly being poured ontocrushed ice. The resulting slurry was twice extracted into EtOAc (2 Lfor each extraction). The organic portions were combined and washed withbrine (50 mL) before being dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide the intermediate sulfonylchloride as an off white solid (125 g, 75% yield). ¹H NMR (400 MHz,CDCl₃) δ ppm 8.61 (1 h, t, J=1.7 Hz), 8.35-8.31 (2H, m), 7.90 (1H, t,J=7.9 Hz), 3.15 (3H, s).

N-Hydroxy-3-methanesulfonylbenzene-1-sulfonamide

To a solution of aqueous hydroxylamine (16 mL of a 50% aqueous solution,245 mmol) in THF (150 mL) and water (25 mL) cooled to −5° C. was slowlyadded 3-methanesulfonylbenzene-1-sulfonyl chloride (25 g, 98 mmol) whilemaintaining a reaction temperature of less than 10° C. The reaction wasmaintained at this temperature until substantially complete consumptionof the sulfonyl chloride was observed (about 5 min), after which timethe reaction was diluted with DCM (250 mL), the organic portion wasseparated and washed twice with 50 mL of water. The aqueous extractswere combined and rewashed twice with DCM (250 mL for each wash). All ofthe organic portions were combined, dried over sodium sulfate, filteredand concentrated under reduced pressure to provide the title compound asa beige solid. Trituration was carried out using heptanes:EtOAc (1:1;v:v) to provide the title compound as a beige solid (14 g, 56% yield).LC-MS t_(R)=0.90 min; High Resolution Mass Spectroscopy (HRMS):theoretical (C₇H₉NO₅S₂)=249.9844, measured=249.9833; ¹H NMR (500 MHz,DMSO-d₆) δ ppm 9.85 (2H, q, J=3.3 Hz), 8.31 (1H, t, J=1.6 Hz), 8.28 (1H,dt, J=7.8, 1.3 Hz), 8.14-8.19 (1H, m), 7.93 (1H, t, J=7.9 Hz), 3.32 (3H,s).

Example 15 Preparation of N-Hydroxy-5-methyl-1,2-oxazole-4-sulfonamide(3)

To a solution of hydroxylamine (0.45 mL of a 50% aqueous solution; 13.7mmol) in THF (6 mL) and water (1 mL) cooled to 0° C. was added5-methyl-1,2-oxazole-4-sulfonyl chloride (1.0 g, 5.5 mmol) portionwiseso as to maintain the temperature below 10° C. The reaction was stirredfor 10 minutes, after which time LC-MS showed complete consumption ofthe sulfonyl chloride. The reaction was diluted with DCM (50 mL) and theorganic portion was separated and washed with water (10 mL). The organicportion was dried over sodium sulfate, filtered and concentrated underreduced pressure. The product was triturated with diethyl ether toprovide the title compound as a off white solid (0.45 g, 46% yield).LC-MS t_(R)=0.66 min; HRMS: theoretical (C₄H₆N₂O₄S)=176.997,measured=176.9972; ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.83 (1H, s), 9.68(1H, br. s.), 8.77 (1H, s), 2.64 (3H, s).

Example 16 Preparation of N-Hydroxy-1-benzofuran-7-sulfonamide (4)

To a solution of hydroxylamine (0.76 mL of a 50% aqueous solution; 11.5mmol) in THF (12 mL) and water (2 mL) cooled to 0° C. was added1-benzofuran-7-sulfonyl chloride (1 g, 4.6 mmol) portionwise so as tomaintain the temperature below 10° C. The reaction was stirred for 10minutes, after which time TLC (heptane:EtOAc) showed substantiallycomplete consumption of the sulfonyl chloride. The reaction was dilutedwith DCM (25 mL) and the organic portion was separated and washed withwater (10 mL). The organic portion was dried over sodium sulfate,filtered and concentrated under reduced pressure. Trituration withheptane provided the title compound as an off white solid (0.63 g, 64%yield). LC-MS t_(R)=1.32; ¹H NMR (500 MHz, DMSO) δ 9.75 (d, J=3.0 Hz,1H), 9.66 (1H, d, J=3.1 Hz), 8.18 (1H, d, J=2.2 Hz), 8.01 (1H, d, J=6.8Hz), 7.72 (1H, d, J=7.7 Hz), 7.45 (1H, t, J=7.7 Hz), 7.14 (1H, d, J=2.2Hz).

Example 17 Preparation of4-(Hydroxysulfamoyl)-N-(propan-2-yl)thiophene-2-carboxamide (5)N-(Propan-2-yl)thiophene-2-carboxamide

A solution of propan-2-amine (9.7 mL, 112.6 mmol) in DCM (150 mL) wascooled at 0° C. with stirring under nitrogen. Thiophene-2-carbonylchloride (11.0 mL, 102.3 mmol) was added dropwise and then ethyldiisopropylamine (19.5 mL, 112.6 mmol) was added. The reaction mixturewas left to warm to a temperature of about 21° C. and stirring wascontinued for 18 hours after which time the reaction mixture was furtherdiluted with DCM (100 mL) and washed with 1M HCl solution (2×50 mL),water (1×50 mL), saturated NaHCO₃ solution (1×25 mL) and brine (2×25 mL)before the organic layer was dried over magnesium sulfate, filtered andconcentrated under reduced pressure to provideN-(propan-2-yl)thiophene-2-carboxamide as a white solid (18.1 g, 99.2%yield). LC-MS t_(R)=1.43 min; ¹H NMR (500 MHz, chloroform-d) δ ppm7.54-7.46 (1H, m), 7.43 (1H, d, J=5.0 Hz), 7.04 (1H, t, J=4.3 Hz), 6.00(1H, br s), 4.31-4.16 (1H, m, J=6.6 Hz), 1.24 (6H, d, J=6.7 Hz).

5-[(Propan-2-yl)carbamoyl]thiophene-3-sulfonyl chloride

A solution of N-(propan-2-yl)thiophene-2-carboxamide (17.3 g, 102.3mmol) in chlorosulfonic acid (68.1 mL, 1023.2 mmol) was heated at 100°C. for 2 hours, after which time the solution was allowed to cool to atemperature of about 21° C. and was carefully poured onto ice (500 mL).The aqueous solution was extracted into DCM (2×250 mL) and the combinedorganic portions were dried over magnesium sulfate, filtered andconcentrated under reduced pressure to provide the desired compound as amixture with 5-[(propan-2-yl)carbamoyl]thiophene-2-sulfonyl chloridewhich was separated with a silica gel column eluting with heptanes:EtOActo provide the product as a white solid (9.9 g, 36.1% yield). LC-MSt_(R)=1.85 min; ¹H NMR (250 MHz, chloroform-d) δ ppm 8.33 (1H, d, J=1.4Hz), 7.82 (1H, d, J=1.4 Hz), 6.24 (1H, d, J=6.5 Hz), 4.27 (1H, qd,J=6.6, 14.4 Hz), 1.30 (6H, d, J=6.7 Hz).

4-(Hydroxysulfamoyl)-N-(propan-2-yl)thiophene-2-carboxamide

To a solution of hydroxylamine (6.1 mL of a 50% aqueous solution; 95.3mmol) in THF (30 mL) and water (10 mL) cooled to 0° C. was added5-[(propan-2-yl)carbamoyl]thiophene-3-sulfonyl chloride (9.9 g, 36.9mmol) as a solution in THF (30 mL) dropwise so as to maintain thetemperature below 10° C. The reaction was stirred for 10 minutes, afterwhich time LC-MS showed complete consumption of the sulfonyl chloride.The reaction was diluted with DCM (100 mL) and the organic portion wasseparated and washed with water (50 mL). The aqueous layer wasre-extracted with DCM (2×50 mL) and EtOAc (50 mL). All the organicportions were combined, dried over sodium sulfate, filtered andconcentrated under reduced pressure. Trituration with heptanes:EtOAcprovided the title compound as a white solid (6.4 g, 65.4% yield). LC-MSt_(R)=1.22 min; HRMS: theoretical (C₈H₁₂N₂O₄S₂)=263.0160,measured=263.0164; ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.69 (1H, d, J=3.2Hz), 9.59 (1H, d, J=3.2 Hz), 8.61 (1H, d, J=7.6 Hz), 8.34 (1H, d, J=1.4Hz), 8.10 (1H, d, J=1.1 Hz), 3.92-4.16 (1H, m), 1.15 (6H, d, J=6.6 Hz).

Example 18 Preparation of N-Hydroxy-1-benzofuran-3-sulfonamide (6)1-Benzofuran-3-sulfonyl chloride

1-Benzofuran-3-sulfonyl chloride was synthesized according to themethods disclosed in Park et al., Bioorg. Med. Chem. Letters18(14):3844-3847 (2008). Benzofuran (4.2 g, 35.6 mmol) was added to asolution of sulfuryl chloride (4.9 mL, 60.4 mmol) in DMF (13 mL) at 0°C. and the reaction was heated to 85° C. for 3 hours. After the reactionwas substantially complete, as determined by TLC (heptanes:EtOAc), thereaction was cooled to a temperature of about 21° C. and poured ontoice. The product was extracted into EtOAc (2×50 mL) and dried oversodium sulfate, filtered and concentrated under reduced pressure. Theproduct was chromatographed with a silica gel column eluting withheptanes:EtOAc to provide the sulfonyl chloride as a yellow oil (0.27 g,3.5% yield). LC-MS t_(R)=2.06 min; ¹H NMR (500 MHz, DMSO-d₆) δ ppm 7.93(1H, s), 7.68-7.81 (1H, m), 7.54 (1H, dd, J=8.1, 0.9 Hz), 7.17-7.38 (2H,m).

N-Hydroxy-1-benzofuran-3-sulfonamide

To a solution of hydroxylamine (0.1 mL of a 50% aqueous solution; 3.0mmol) in THF (1.25 mL) and water (0.25 mL) cooled to 0° C. was added1-benzofuran-3-sulfonyl chloride (0.26 g, 1.2 mmol) portionwise so as tomaintain the temperature below 10° C. The reaction was stirred for 10minutes, after which time LC-MS showed complete consumption of thesulfonyl chloride. The reaction was diluted with DCM (10 mL) and theorganic portion was separated and washed with water (5 mL). The organicportion was dried over sodium sulfate, filtered and concentrated underreduced pressure. The product was chromatographed with a silica gelcolumn eluting with heptanes:EtOAc followed by trituration withheptanes:DCM to provide the title compound as a yellow solid (0.03 g,12% yield). LC-MS t_(R)=1.45; ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.75 (2H,s), 8.68 (1H, s), 7.86 (1H, d, J=7.7 Hz), 7.76 (1H, d, J=8.2 Hz),7.36-7.57 (2H, m).

Example 19 Preparation ofN-Hydroxy-5-methyl-2-(trifluoromethyl)furan-3-sulfonamide (7)

To a solution of hydroxylamine (0.66 mL of a 50% aqueous solution; 10.1mmol) in THF (6 mL) and water (1 mL) cooled to 0° C. was added5-methyl-2-(trifluoromethyl)furan-3-sulfonyl chloride (1 g, 4.0 mmol)portionwise so as to maintain the temperature below 10° C. The reactionwas stirred for 5 minutes, after which time LC-MS showed completeconsumption of the sulfonyl chloride. The reaction was diluted with DCM(25 mL) and the organic portion was separated and washed with water (10mL). The organic portion was dried over sodium sulfate, filtered andconcentrated under reduced pressure. The product was triturated withheptane to provide the title compound as an off white solid (0.7 g, 71%yield). LC-MS t_(R)=1.64 min; ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.81 (1H,d, J=3.3 Hz), 9.68 (1H, d, J=3.2 Hz), 7.37 (1H, s), 2.60 (3H, s).

Example 20 Preparation ofN-Hydroxy-5-methanesulfonylthiophene-3-sulfonamide (8)5-Methanesulfonylthiophene-3-sulfonyl chloride and5-methanesulfonylthiophene-2-sulfonyl chloride

A solution of 2-methanesulfonylthiophene (1.0 g, 6.2 mmol) inchlorosulfonic acid (2.9 mL, 43.2 mmol) was heated at 90° C. for 1 hour,after which time the solution was allowed to cool to a temperature ofabout 21° C. and was carefully poured onto ice (20 mL). The aqueoussolution was extracted into DCM (2×25 mL). The organic portions werecombined, dried over sodium sulfate, filtered and concentrated underreduced pressure to provide the sulfonyl chloride as a mixture with5-methanesulfonylthiophene-2-sulfonyl chloride. The mixture waschromatographed with a silica gel column eluting with heptanes:EtOAconly partially separated the two isomers and the sulfonyl chloride wastaken on to the next step (0.5 g, 31% yield as a 85:15 mixture with theother isomer). LC-MS t_(R)=1.67 min; ¹H NMR (500 MHz, DMSO-d₆) δ ppm7.99 (1H, d, J=1.6 Hz), 7.69 (1H, d, J=1.6 Hz), 3.36 (3H, s).

N-Hydroxy-5-methanesulfonylthiophene-3-sulfonamide

To a solution of hydroxylamine (0.3 mL of a 50% aqueous solution; 4.8mmol) in THF (6 mL) and water (1 mL) cooled to 0° C. was added a mixtureof 5-methanesulfonylthiophene-3-sulfonyl chloride and5-methanesulfonylthiophene-2-sulfonyl chloride (85:15 by LC-MS) (0.5 g,1.9 mmol) portionwise so as to maintain the temperature below 10° C. Thereaction was stirred for 5 minutes, after which time LC-MS showedcomplete consumption of the sulfonyl chloride. The reaction was dilutedwith DCM (10 mL) and the organic portion was separated and washed withwater (5 mL). The organic portion was dried over sodium sulfate,filtered and concentrated under reduced pressure. The product waschromatographed by reverse phase neutral preparative HPLC to provide thetitle compound as a white solid (0.07 g, 14% yield). LC-MS t_(R)=0.94;¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.85 (1H, d, J=2.8 Hz), 9.78 (1H, d,J=2.8 Hz), 8.65 (1H, d, J=1.6 Hz), 7.98 (1H, d, J=1.4 Hz), 3.46 (3H, s).

Example 211-Acetyl-5-bromo-N-hydroxy-2,3-dihydro-1H-indole-6-sulfonamide (9)1-(5-Bromo-2,3-dihydro-1H-indol-1-yl)ethan-1-one

To a solution of 5-bromo-2,3-dihydro-1H-indole (1.5 g, 7.5 mmol) inacetic acid (12 mL) was added acetyl chloride (3.57 g, 45.4 mmol). Thereaction was heated to 90° C. until consumption of the starting materialwas substantially complete (c.a. 1 h) and the solvents removed underreduced pressure. The organic portion was diluted in ethyl acetate andwashed with sodium bicarbonate solution. The combined organics weredried over sodium sulfate, filtered and concentrated under reducedpressure to provide the title compound as a brown solid (1.76 g, 99.99%yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 7.96 (1H, d, 8.7 Hz), 7.40 (1H,d, 0.8 Hz), 7.30 (1H, dd, 8.5, 2.0 Hz), 4.09 (2H, t, 8.6 Hz), 3.14 (2H,t, 8.5 Hz), 2.14 (3H, s).

1-Acetyl-5-bromo-2,3-dihydro-1H-indole-6-sulfonyl chloride

1-(5-Bromo-2,3-dihydro-1H-indol-1-yl)ethan-1-one (1.2 g, 5.0 mmol) andchlorosulfonic acid (3.5 g, 30 mmol) were heated in a sealed tube to 80°C. for 18 hours. The reaction was quenched by pouring onto ice and theresulting solid was filtered and dried under reduced pressure thenchromatographed with a silica gel column eluting with 40% heptane:ethylacetate to provide the title compound as an off white solid (0.95 g, 56%yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 8.60 (1H, s), 7.37 (1H, s), 4.09(2H, t, 8.6 Hz), 3.11 (2H, t, 8.5 Hz), 2.14 (3H, s).

1-Acetyl-5-bromo-N-hydroxy-2,3-dihydro-1H-indole-6-sulfonamide

To a solution of aqueous hydroxylamine (1.6 mL, 3.7 mmol, 50% aqueous),in THF (2.5 mL) and water (0.5 mL) at −10° C. was added1-acetyl-5-bromo-2,3-dihydro-1H-indole-6-sulfonyl chloride (0.5 g, 1.48mmol) portion wise maintaining and internal temperature of −5° C.Stirring was continued at low temperature until complete consumption ofthe sulfonyl chloride was observed by LC-MS. Diethyl ether was added andthe reaction was washed with a 10% citric acid solution. The organicswere dried over Na₂SO₄, filtered and concentrated under reduced pressureto provide1-acetyl-5-bromo-N-hydroxy-2,3-dihydro-1H-indole-6-sulfonamide as an offwhite solid (0.32 g, 66% yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm9.44-9.76 (2H, m), 8.72 (1H, s), 7.68 (1H, s), 4.16 (2H, t, 8.6 Hz),3.22 (2H, t, 8.8 Hz), 2.17 (3H, s); predicted [M−H]⁻=332.9545; observed[M−H]⁻=332.9553.

Example 22 2-Chloro-N-hydroxy-5-(hydroxymethyl)benzene-1-sulfonamide(10) 2-Chloro-5-(hydroxymethyl)aniline

To a solution of 1-chloro-4-(hydroxymethyl)-2-nitrobenzene (4.5 g, 24mmol) in EtOH (23 mL) and water (4.5 mL) was added iron (3.45 g, 84mmol) and HCl (9 drops). The reaction was heated to 85° C. for 4 hours.The cooled reaction mixture was filtered through CELITE, washed withEtOAc and concentrated under reduced pressure and used directly in thenext step (3.5 g, 95% yield). ¹H NMR (250 MHz, DMSO-d₆) δ 7.09 (1H, d,8.1 Hz), 6.76 (1H, d, 2.0 Hz), 6.47 (1H, dd, 8.1, 1.9 Hz), 5.10 (1H, t,5.7 Hz), 4.34 (2H, d, 5.8 Hz).

2-Chloro-5-(hydroxymethyl)benzene-1-sulfonyl chloride

To a solution of 2-chloro-5-(hydroxymethyl)aniline (0.5 g, 3.1 mmol) inacetic acid (3.2 mL) and HCl (0.8 mL) cooled to 0° C. was added sodiumnitrite (0.24 g, 3.5 mmol) portion wise maintaining an internaltemperature <5° C. The reaction mixture was allowed to stir at 0° C. for1 hour. Simultaneously, CuCl₂.H₂O (0.5 g, 3.1 mmol) was suspended inAcOH:water (3.2 mL:1.6 mL) at 0° C. and stirred at 0° C. until all CuCl₂was in solution. SO₂ gas was condensed into a flask at −78° C. via theaid of a cold finger and the diazo compound and CuCl₂ solution added andthe reaction warmed to 0° C. The reaction was allowed to warm to atemperature of about 25° C. over 2 hours. The reaction was quenched byaddition to ice and extracted into DCM (2×10 mL). The organics weredried over sodium sulfate, filtered and concentrated under reducedpressure to provide the title compound as a yellow oil. The sulfonylchloride was chromatographed with a silica gel column eluting with DCMto provide the sulfonyl chloride as a yellow oil (0.2 g, 26% yield). ¹HNMR (250 MHz, chloroform-d) δ 8.14 (1H, d, 1.2 Hz), 7.41-7.83 (2H, m),4.79 (2H, s).

2-Chloro-N-hydroxy-5-(hydroxymethyl)benzene-1-sulfonamide

To a solution of hydroxylamine (0.45 mL of a 50% aqueous solution; 15.5mmol) in tetrahydrofuran (5 mL) and water (1 mL) cooled to −5° C. wasadded 2-chloro-5-(hydroxymethyl)benzene-1-sulfonyl chloride (1.25 g, 5.1mmol) as a solution in tetrahydrofuran (2.5 mL) dropwise so as tomaintain the temperature below 0° C. The reaction was stirred until TLCindicated substantially complete consumption of starting material(approximately 30 minutes). The reaction was diluted withdichloromethane (50 mL) and the organic portion was washed with water (1mL) before being separated and dried over sodium sulfate, filtered andconcentrated under reduced pressure. Trituration with n-pentane providedthe N-hydroxy-5-methylfuran-2-sulfonamide as an off-white solid (0.37 g,30% yield). ¹H NMR (300 MHz, DMSO) δ 9.74 (2H, q, 3.0 Hz), 7.98 (1H, d,1.4 Hz), 7.60 (2H, dt, 8.2, 5.0 Hz), 5.51 (1H, s), 4.57 (2H, s).

Example 231-Acetyl-5-chloro-N-hydroxy-2,3-dihydro-1H-indole-6-sulfonamide (11)1-(5-Chloro-2,3-dihydro-1H-indol-1-yl)ethan-1-one

To a solution of 5-chloro-2,3-dihydro-1H-indole (6.0 g, 39 mmol) inacetic acid (60 mL) was added acetyl chloride (18.4 g, 23 mmol). Thereaction was heated to 80° C. until consumption of the starting materialwas substantially complete (c. a. 1 h) and the solvents removed underreduced pressure. The organic portion was diluted into ethyl acetate(200 mL) and washed with sodium bicarbonate solution (2×100 mL). Thecombined organics were dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide1-(5-chloro-2,3-dihydro-1H-indol-1-yl)ethan-1-one as a brown solid (7.1g, 93% yield). ¹H NMR (400 MHz, DMSO) δ 8.00 (1H, d, 8.6 Hz), 7.28 (1H,s), 7.18 (12H, dd, 8.6, 2.0 Hz), 4.10 (2H, t, 8.6 Hz), 3.13 (2H, t, 8.6Hz), 2.14 (3H, s).

1-Acetyl-5-chloro-2,3-dihydro-1H-indole-6-sulfonyl chloride

1-(5-chloro-2,3-dihydro-1H-indol-1-yl)ethan-1-one (7 g, 36 mmol) andchlorosulfonic acid (16.68 g, 143 mmol) were heated to 70° C. for 18hours. The reaction was quenched by addition to ice and the resultingsolid obtained was extracted into ethyl acetate (250 mL). The resultingsolution was washed with water (2×100 mL) and the organic portion wasdried over sodium sulfate, filtered and concentrated under reducedpressure to provide the acetyl-5-chloro-2,3-dihydro-1H-indole-6-sulfonylchloride. The product was chromatographed with a silica gel columneluting with 40-50% ethyl acetate:hexane to provide1-acetyl-5-chloro-2,3-dihydro-1H-indole-6-sulfonyl chloride as a offwhite solid (7.2 g, 68.4% yield). ¹H NMR (400 MHz, DMSO) δ 8.56 (1H, s),7.19 (1H, s), 4.09 (2H, t, 8.6 Hz), 3.10 (2H, t, 8.5 Hz), 2.14 (3H, s).

1-Acetyl-5-chloro-N-hydroxy-2,3-dihydro-1H-indole-6-sulfonamide

To a solution of hydroxylamine (1.8 mL of a 50% aqueous solution; 61.1mmol) in tetrahydrofuran (40 mL) and water (5 mL) cooled to −5° C. wasadded 1-acetyl-5-chloro-2,3-dihydro-1H-indole-6-sulfonyl chloride (4.0g, 13.6 mmol) as a solution in tetrahydrofuran (10 mL) dropwise so as tomaintain the temperature below 0° C. The reaction was stirred for 30minutes, and TLC indicated substantially complete consumption ofstarting material. The reaction was diluted with water (5 mL) and theresulting solid collected under vacuum and washed further with water(2×10 mL) before drying under vacuum to provide1-acetyl-5-chloro-N-hydroxy-2,3-dihydro-1H-indole-6-sulfonamide as awhite solid (3.0 g, 76% yield). ¹H NMR (400 MHz, DMSO) δ 9.65 (1H, s),9.55 (1H, s), 8.72 (1H, s), 7.68 (1H, s), 4.15 (2H, t, 8.6 Hz), 3.22(2H, t, 8.5 Hz), 2.17 (3H, s); predicted [M−H]⁻=289.005; observed[M−H]⁻=289.0059.

Example 24 4,5-Dichloro-N-hydroxythiophene-2-sulfonamide (12)

To a solution of hydroxylamine (0.655 mL of a 50% aqueous solution; 10.0mmol) in tetrahydrofuran (6 mL) and water (1 mL) cooled to −5° C. wasadded 4,5-dichlorothiophene-2-sulfonyl chloride (1.0 g, 4.0 mmol) as asolution in tetrahydrofuran (1 mL) dropwise so as to maintain thetemperature below 0° C. The reaction was stirred until TLC indicatedsubstantially complete consumption of starting material (approximately10 minutes). The reaction was diluted with diethyl ether (20 mL) and theorganic portion was washed with citric acid solution (2×1 mL) beforebeing separated and dried over sodium sulfate, filtered and concentratedunder reduced pressure. Trituration with diethyl ether:heptane provided4,5-dichloro-N-hydroxythiophene-2-sulfonamide as a-white solid (0.35 g,38% yield). ¹H NMR (250 MHz, DMSO-d₆) δ 10.06 (1H, d 2.9 Hz), 10.00 (1H,d, 2.7 Hz), 7.73 (1H, s); predicted [M−H]⁻=245.8853; observed[M−H]⁻=245.8845.

Example 25 N-Hydroxy-6-methoxy-1-benzofuran-2-sulfonamide (13)2-(2-Formyl-5-methoxyphenoxy)acetic acid

An aqueous solution of sodium hydroxide (20 mL, 5.2 g, 131 mmol) wasadded to a mixture of 2-hydroxy-4-methoxybenzaldehyde (10 g, 65 mmol),chloroacetic acid (6.2 g, 65 mmol) and water (80 mL). The mixture wasstirred slowly before heating under reflux for 16 hours after which timethe reaction mixture was allowed to cool to a temperature of about 25°C. where upon the reaction mixture was acidified with concentrated HClto pH 3. The resulting acidic solution was extracted into ethyl acetate(3×50 mL) before being dried over sodium sulfate and concentrated underreduced pressure to provide the desired compound as a brown oil whichwas used directly in the next step (11.5 g, 83% yield). LC-MS t_(R)=0.75min, [M+H]⁺=211.29

6-Methoxy-1-benzofuran

Sodium acetate (21.0 g, 254 mmol) was added to a mixture of2-(2-formyl-5-methoxyphenoxy)acetic acid (11.4 g, 54 mmol) in aceticanhydride (75 mL) and acetic acid (75 mL) and the reaction was heated to140° C. for 18 hours. The reaction mixture was allowed to cool at atemperature of about 25° C. before addition of water (100 mL) and theresulting aqueous solution was extracted with ethyl acetate (3×20 mL).The combined organic phases were washed with saturated sodiumbicarbonate solution (3×30 mL), dried over sodium sulfate andconcentrated under reduced pressure to provide the compound as a brownoil. The oil was chromatographed with a silica gel column eluting with0.5% ethyl acetate in hexane to provide pale yellow oil (1.6 g, 20%)which was confirmed by ¹H NMR. ¹H NMR (400 MHz, CDCl₃) δ 7.53 (1H, t,3.3 Hz) 7.45 (1H, d, 8.5 Hz), 7.04 (1H, d, 2.0 Hz), 6.88 (1H, dd, 8.5,2.3 Hz), 6.70 (1H, dd, 2.2, 0.9 Hz), 3.86 (3H, s).

6-Methoxy-1-benzofuran-2-sulfonyl chloride

To a solution of 6-methoxy-1-benzofuran (1.6 g, 10.8 mmol) in THF (20mL) at −78° C. was added n-BuLi (2.5 M solution in hexanes, 4.8 mL, 11.8mmol) drop wise and stirring was continued at this temperature for 1hour. Sulfur dioxide gas was bubbled into the reaction mixturemaintaining the temperature of −50° C. for 1 hour and stirring wascontinued at this temperature for a further 1 hour. To this solution wasadded N-chlorosuccinamide (2.2 g, 16 mmol) and the reaction mixture waswarmed from at −20° C. to a temperature of about 25° C. over 18 hours.The reaction mixture was quenched with water (25 mL) and the organicsextracted into ethyl acetate (2×20 mL), dried over sodium sulfate,filtered and concentrated under reduced pressure. The sulfonyl chloridewas chromatographed with a silica gel column eluting with 2% ethylacetate in hexane to provide a green solid (0.8 g, 30% yield). ¹H NMR(400 MHz, CDCl₃) δ 7.61 (1H, d, 8.8 Hz), 7.59 (1H, d, 0.9 Hz), 7.09 (1H,d, 2.1 Hz), 7.05 (1H, dd, 8.8, 2.2 Hz), 3.91 (s, 3H).

N-Hydroxy-6-methoxy-1-benzofuran-2-sulfonamide

To a solution of aqueous hydroxylamine (1.6 mL of a 50% solution, 33.0mmol) in THF (18 mL) was added 6-methoxy-1-benzofuran-2-sulfonylchloride solution (2.3 g, 9.3 mmol) in THF (6 mL) drop wise at 0° C. Thereaction was stirred for 30 minutes, and TLC indicated substantiallycomplete consumption of the starting material. The reaction mixture wasdiluted with diethyl ether (50 mL) and washed with water (2×15 mL),dried over sodium sulfate and concentrated under reduced pressure toprovide the compound which was tritiated using 5% DCM pentane yieldingthe desired product as an off white solid (0.9 g, 40% yield). ¹H NMR(400 MHz, DMSO) δ 10.13 (1H, d, 2.2 Hz), 9.80 (1H, d, 1.9 Hz), 7.69 (1H,d, 8.7 Hz), 7.63 (1H, d, 0.9 Hz), 7.32 (1H, d, 2.0 Hz), 7.03 (1H, dd,8.7, 2.2 Hz), 3.85 (3H, s).

Example 26 2-Fluoro-N-hydroxy-4-methylbenzene-1-sulfonamide (14)

To a solution of hydroxylamine (1.5 mL of a 50% aqueous solution; 23.9mmol) in tetrahydrofuran (12 mL) and water (2 mL) cooled to −10° C. wasadded 2-fluoro-4-methylbenzene-1-sulfonyl chloride (2.0 g, 9.6 mmol)portion wise so as to maintain the temperature below 0° C. The reactionwas stirred for 5 minutes, after which time LC-MS indicated completeconsumption of starting material. The reaction was diluted with diethylether (30 mL) and the organic portion was washed with 10% citric acidsolution (10 mL) before being separated and dried over magnesiumsulfate, filtered and concentrated under reduced pressure. Triturationwith heptanes:diethyl ether provided the N-hydroxy-sulfonamide as anoff-white solid (1.06 g, 58% yield). ¹H NMR (500 MHz, DMSO-d₆) δ 9.67(2H, s), 7.69 (1H, t, 7.8 Hz), 7.29 (1H, d, 11.5 Hz), 7.23 (1H, d, 8.0Hz), 2.40 (3H, s); predicted [M−H]⁻=204.0131; observed [M−H]⁻=204.0175.

Example 27 N-Hydroxy-2,1,3-benzothiadiazole-5-sulfonamide (15)

To a solution of aqueous hydroxylamine (0.7 mL of a 50% solution, 10.65mmol) in tetrahydrofuran (6 mL) and water (1 mL) cooled to −5° C. wasslowly added 2,1,3-benzothiadiazole-5-sulfonyl chloride (1.0 g, 4.3mmol) maintaining a reaction temperature of less than 10° C. Thereaction was maintained at this temperature until complete consumptionof the sulfonyl chloride was observed by LC-MS (about 5 min.), afterwhich time the reaction was diluted with ethyl acetate (20 mL) and theorganic portion was separated, washed with water (2×5 mL), dried oversodium sulfate, filtered and concentrated under reduced pressure toprovide the N-hydroxysulfonamide as an orange solid, further washingwith sodium bicarbonate solution (10 mL) was required to remove sulfinicacid impurities. Trituration was carried out using heptanes:DCM (9:1,v:v) to provide the title compound as a orange solid (0.53 g, 54%yield). ¹H NMR (500 MHz, DMSO-d₆) δ 9.94 (1H, d, 3.2 Hz), 9.84 (1H, d,3.2 Hz), 8.62-8.53 (1H, m), 8.42-8.32 (1H, m), 8.04 (1H, dd, 9.2, 1.7Hz).

Example 28 N-Hydroxy-4-methanesulfonylthiophene-2-sulfonamide (16)3-(Methylsulfanyl)thiophene

To a solution of 3-bromothiophene (3.3 g, 0.02 mol) in heptane (30 mL)at −40° C. was added a solution of n-butyllithium (8.5 mL of a 2.5Msolution in hexanes) dropwise. Tetrahydrofuran (3 mL) was added to theflask and the 3-lithiothiophene precipitated as a white solid and thereaction mixture was warned to a temperature of about 25° C. Methyldisulfide (1.97 mL, 0.02 mol) was added dropwise to the resultingsolution and the reaction mixture was stirred for 1 hour at atemperature of about 25° C. Water (10 mL) was added to the flask, theorganic layer separated, dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide3-(methylsulfanyl)thiophene as a colorless oil (2.6 g, 98% yield). ¹HNMR (500 MHz, chloroform-d) δ ppm 7.34 (1H, dd, J=5.0, 3.0 Hz), 7.01(1H, dd, J=5.0, 1.3 Hz), 6.99 (1H, dd, J=3.0, 1.3 Hz), 2.49 (3H, s).

3-Me thanesulfonylthiophene

To a solution of 3-(methylsulfanyl)thiophene (2.6 g, 19.96 mmol) inacetic acid (20 mL) was added hydrogen peroxide (4.53 mL of a 30%aqueous solution, 39.93 mmol). The reaction was heated to reflux for 3hours and allowed to cool to a temperature of about 25° C. for 18 hoursbefore the acetic acid was removed under reduced pressure. The resultingorganics were dissolved in ethyl acetate (30 mL) and the whole waswashed with saturated sodium bicarbonate solution (2×10 mL). The organiclayer was dried over sodium sulfate, filtered and concentrated underreduced pressure to provide a yellow oil which solidified on standingand was used directly in the next step (2.2 g, 67.9% yield). ¹H NMR (500MHz, chloroform-d) δ ppm 8.11 (1H, dd, J=3.1, 1.2 Hz), 7.49 (1H, dd,J=5.1, 3.1 Hz), 7.43 (1H, dd, J=5.2, 1.3 Hz), 3.11 (3H, s).

4-Methanesulfonylthiophene-2-sulfonyl chloride

Chlorosulfonic acid (8.11 mL, 0.12 mol) was added to3-methanesulfonylthiophene (2.2 g, 13.56 mmol) and the suspension washeated to 90° C. for 1 hour. The solution was allowed to cool to atemperature of about 25° C. and poured onto ice (100 mL). The sulfonylchloride was extracted into dichloromethane (3×50 mL) dried over sodiumsulfate, filtered and concentrated under reduced pressure to provide thetitle compound as a fawn solid (3.16 g, 89% yield). ¹H NMR (500 MHz,chloroform-d) δ ppm 8.50 (1H, d, J=1.6 Hz), 8.17 (1H, d, J=1.6 Hz), 3.19(3H, s).

N-Hydroxy-4-methanesulfonylthiophene-2-sulfonamide

To a solution of aqueous hydroxylamine (2.03 mL of a 50% aqueoussolution, 30.68 mmol) in tetrahydrofuran (12 mL) and water (3 mL) cooledto −5° C. was slowly added 4-methanesulfonylthiophene-2-sulfonylchloride (3.2 g, 12.27 mmol) maintaining a reaction temperature of lessthan 10° C. The reaction was maintained at this temperature untilsubstantially complete consumption of the sulfonyl chloride was observedby TLC (about 15 min.), after which time the reaction was diluted withdiethyl ether (25 mL) and the organic portion was separated, washed withwater (2×10 mL), dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the N-hydroxysulfonamide as an offwhite solid. Trituration was carried out using diethyl ether to providethe title compound as an off white solid (1.34 g, 42.4% yield). LC-MSt_(R)=0.91 min, [M−H]⁻=256; ¹H NMR (500 MHz, DMSO-d₆) δ ppm 10.02 (1H,d, J=3.0 Hz), 9.96 (1H, d, J=3.2 Hz), 8.73 (1H, d, J=1.6 Hz), 7.98 (1H,d, J=1.6 Hz), 3.33 (3H, s).

Example 29 5-Bromo-N-hydroxy-2-methoxybenzene-1-sulfonamide (17)

To a solution of aqueous hydroxylamine (2.89 mL of a 50% solution, 43.78mmol) in tetrahydrofuran (30 mL) and water (5 mL) cooled to −5° C. wasslowly added 5-bromo-2-methoxybenzene-1-sulfonyl chloride (5 g, 17.51mmol) maintaining a reaction temperature of less than 10° C. Thereaction was maintained at this temperature until complete consumptionof the sulfonyl chloride was observed by LC-MS (about 5 min), afterwhich time the reaction was diluted with dichloromethane (50 mL) and theorganic portion was separated, washed with water (2×10 mL), dried oversodium sulfate, filtered and concentrated under reduced pressure toprovide the N-hydroxysulfonamide as an off white solid. Trituration wascarried out using heptanes:DCM (1:1, v:v) to provide the title compoundas an off white solid (2.94 g, 60% yield). LC-MS t_(R)=1.66 min,[M−H]⁻=281; ¹H NMR (500 MHz, DMSO-d₆) δ 9.68 (s, 1H), 9.39-9.17 (m, 1H),7.85 (dd, J=8.9, 2.6 Hz, 1H), 7.80 (d, J=2.5 Hz, 1H), 7.24 (d, J=8.9 Hz,1H), 3.90 (s, 3H).

Example 30 4-Chloro-N-hydroxy-2,5-dimethylbenzene-1-sulfonamide (18)

To a solution of aqueous hydroxylamine (3.45 mL of a 50% solution, 52.28mmol) in tetrahydrofuran (30 mL) and water (5 mL) cooled to −5° C. wasslowly added 4-chloro-2,5-dimethylbenzene-1-sulfonyl chloride (5 g,20.91 mmol) maintaining a reaction temperature of less than 10° C. Thereaction was maintained at this temperature until complete consumptionof the sulfonyl chloride was observed by LC-MS (about 5 min), afterwhich time the reaction was diluted with dichloromethane (50 mL) and theorganic portion was separated, washed with water (2×10 mL), dried oversodium sulfate, filtered and concentrated under reduced pressure toprovide the N-hydroxysulfonamide as an off white solid. Trituration wascarried out using heptanes:DCM (1:1, v:v) to provide the title compoundas a white solid (3.26 g, 66% yield). LC-MS t_(R)=1.86 min, [M−H]⁻=234;¹H NMR (500 MHz, DMSO-d₆) δ 9.59 (s, 2H), 7.78 (s, 1H), 7.52 (s, 1H),2.55 (s, 3H), 2.36 (s, 3H).

Example 31 N,N-Diethyl-5-(hydroxysulfamoyl)thiophene-2-carboxamide (19)N,N-Diethylthiophene-2-carboxamide

To a solution of diethylamine (4.9 g, 68.2 mmol) in DCM (100 mL) wassequentially added triethylamine (6.9 g, 68.2 mmol) andthiophene-2-carbonyl chloride (10 g, 68.2 mmol) and the resultingsolution was stirred for 8 hours at a temperature of about 25° C. Thereaction mixture was diluted with DCM (50 mL) and washed with water(2×50 mL) and the organic phase was dried over sodium sulfate, filteredand concentrated under reduced pressure to provide the product as abrown liquid (11.0 g, 87% yield). ¹H NMR (400 MHz, CDCl₃) δ 7.42 (1H,dd, 5.0, 1.1 Hz), 7.32 (1H, dd, 3.7, 1.1 Hz), 7.04 (1H, dd, 5.0, 3.6Hz), 3.54 (4H, q, 7.1 Hz), 1.26 (6H, t, 7.1 Hz).

5-(Diethylcarbamoyl)thiophene-2-sulfonyl chloride

To an ice cold solution of N,N-diethylthiophene-2-carboxamide (15.0 g,81.8 mmol) was added chlorosulfonic acid (38.2 g, 327 mmol) drop wise,and the resulting solution was stirred at 0° C. for 30 minutes beforebeing heated to 80° C. for 12 hours. The reaction mixture was quenchedby addition to ice and the resulting acidic solution was extracted intoDCM (20 mL), dried over sodium sulfate filtered and concentrated underreduced pressure to give the sulfonyl chloride as a mixture of isomers.The desired compound was obtained by chromatographing with a silica gelcolumn eluting with 18% EtOAc:hexane (1.9 g, 8% yield). ¹H NMR (400 MHz,CDCl₃) δ 7.79 (1H, d, 4.1 Hz), 7.28 (1H, t, 3.6 Hz), 3.53 (4H, q, 7.1Hz), 1.28 (6H, t, 7.1 Hz).

N,N-Diethyl-5-(hydroxysulfamoyl)thiophene-2-carboxamide

A solution of 5-(diethylcarbamoyl)thiophene-2-sulfonyl chloride (1.8 g,6.3 mmol) in THF (20 mL) was added to a solution of aqueoushydroxylamine (0.5 g, 15.8 mmol) in water (5 mL) and THF (20 mL),maintaining a temperature of −10° C. to −5° C. The resulting reactionwas stirred at this temperature for 40 minutes after which time thereaction was seen to be substantially complete by TLC. The reaction waspoured into ethyl acetate (50 mL) and washed with water (20 mL). Theorganic layer was dried over sodium sulfate, filtered and concentratedunder reduced pressure to give the title compound as an off white solid(1.9 g). The desired N-hydroxysulfonamide was isolated by triturationwith DCM:n-pentane (2:8; v:v) to provide a white solid (1.0 g, 56%yield). ¹H NMR (360 MHz, DMSO-d₆) δ 9.90 (1H, d, 3.2 Hz) 9.85 (1H, d,3.2 Hz) 7.59 (1H, d, 4.1 Hz) 7.45 (1H, d, 4.1 Hz) 3.45 (4H, q, 6.8 Hz)1.16 (6H, t, 6.4 Hz); predicted [M−H]⁻=277.0317; observed[M−H]⁻=277.0316.

Example 32 5-Fluoro-N-hydroxy-2-methylbenzene-1-sulfonamide (20)

To a solution of aqueous hydroxylamine (1.5 mL of a 50% solution, 23.9mmol) in tetrahydrofuran (10 mL) and water (2 mL) cooled to −5° C. wasslowly added a solution of 5-fluoro-2-methylbenzene-1-sulfonyl chloride(2.0 g, 9.6 mmol) in tetrahydrofuran (2 mL) maintaining a reactiontemperature of less than 10° C. The reaction was maintained at thistemperature until complete consumption of the sulfonyl chloride wasobserved by LC-MS (about 10 min), after which time the reaction wasdiluted with diethyl ether (30 mL) and the organic portion was separatedand washed with 1M citric acid solution (10 mL), dried over magnesiumsulfate, filtered and concentrated under reduced pressure to provide theN-hydroxysulfonamide as an off white solid (0.64 g, 32.1% yield). ¹H NMR(250 MHz, DMSO-d₆) δ ppm 9.77 (1H, m), 9.72 (1H, m), 7.59 (1H, dd, 8.7,2.0 Hz), 7.49 (1H, m), 7.46 (1H, m), 2.58 (1H, d, 0.8 Hz); predicted[M−H]⁻=204.0131; observed [M−H]⁻=204.0129.

Example 33 N-Hydroxy-5-(morpholine-4-carbonyl)thiophene-2-sulfonamide(21)

4-[(Thiophen-2-yl)carbonyl]morpholine

To a solution of morpholine (3.3 mL, 37 mmol) and diisopropylethylamine(6.5 mL, 37 mmol) in dichloromethane (50 mL) cooled to 0° C. was addedthiophene-2-carbonyl chloride (5 g, 34 mmol) dropwise. The reactionmixture was stirred for 18 hours at a temperature of about 25° C. beforequenching by the addition of 1N HCl solution (20 mL). The organicportion was washed with water (10 mL) and dried over sodium sulfate,filtered and concentrated under reduced pressure to provide the titlecompound (7.01 g, 65% yield). ¹H NMR (400 MHz, DMSO-d₆) δ ppm 7.76 (1H,dd, 5.0, 1.1 Hz), 7.42 (1H, dd, 3.7, 1.2 Hz), 7.12 (1H, dd, 4.9, 3.7Hz), 3.53-3.71 (8H, m).

5-[(Morpholin-4-yl)carbonyl]thiophene-2-sulfonyl chloride

Chiorosulfonic acid (45.57 mL, 684.4 mmol) was added to4-[(thiophen-2-yl)carbonyl]morpholine (13.5 g, 68.44 mmol) and thesuspension was heated to 100° C. for 2 hours. The solution was allowedto cool to a temperature of about 25° C. and poured onto ice (500 mL).The sulfonyl chloride was extracted into dichloromethane (3×100 mL)dried over sodium sulfate, filtered and concentrated under reducedpressure to provide the title compound as a mixture of isomers (16.5 g)which were separated by silica gel column eluting with 0-50% ethylacetate:heptanes gradient (4.15 g, 20.5% yield). ¹H NMR (250 MHz,DMSO-d₆) δ ppm 7.19 (1H, d, J=3.7 Hz), 7.07 (1H, d, J=3.8 Hz), 3.62 (8H,s). The other isomer (5-(morpholine-4-carbonyl)thiophene-3-sulfonylchloride) was isolated for use in the synthesis of the correspondingN-hydroxysulfonamide (1.4 g, 6.5% yield). ¹H NMR (500 MHz, chloroform-d)δ ppm 8.35 (1H, d, J=1.4 Hz), 7.63 (1H, d, J=1.3 Hz), 3.78 (8H, s).

N-Hydroxy-5-[(morpholin-4-yl)carbonyl]thiophene-2-sulfonamide

To a solution of aqueous hydroxylamine (1.12 mL of a 50% solution, 16.91mmol) in tetrahydrofuran (2 mL) and water (2 mL) cooled to −5° C. wasslowly added a solution of5-[(morpholin-4-yl)carbonyl]thiophene-2-sulfonyl chloride (2 g, 6.76mmol) in tetrahydrofuran (10 mL) maintaining a reaction temperature ofless than 10° C. The reaction was maintained at this temperature untilcomplete consumption of the sulfonyl chloride was observed by LC-MS(about 10 min), after which time the reaction was diluted with diethylether (30 mL) and the organic portion was separated and washed withwater (10 mL), dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the N-hydroxysulfonamide as an offwhite solid. Trituration was carried out using heptane to provide thetitle compound as a white solid (0.24 g, 12.4% yield). LC-MS t_(R)=1.11min, [M+H]⁺=293; ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.90 (1H, s), 9.85 (1H,s), 7.60 (1H, d, J=3.9 Hz), 7.48 (1H, d, J=3.9 Hz), 3.63 (8H, s).

Example 34 5-(hydroxysulfamoyl)-N-(propan-2-yl)thiophene-2-carboxamide(22) N-(Propan-2-yl)thiophene-2-carboxamide

To a solution of isopropylamine (3.2 mL, 37 mmol) anddiisopropylethylamine (5.3 mL, 37 mmol) in dichloromethane (50 mL)cooled to 0° C. was added thiophene-2-carbonyl chloride (5 g, 34 mmol)dropwise. The reaction mixture was stirred for 18 hours at a temperatureof about 25° C. before quenching by the addition of 1N HCl solution. Theorganic portion was washed with water and dried over sodium sulfate,filtered and concentrated under reduced pressure to provide the titlecompound (5.78 g, 99% yield).

5-[(Propan-2-yl)carbamoyl]thiophene-2-sulfonyl chloride

Chlorosulfonic acid (23 mL, 337 mmol) was added toN-(propan-2-yl)thiophene-2-carboxamide (5.7 g, 33.7 mmol) and thesuspension was heated to 100° C. for 90 minutes. The solution wasallowed to cool to a temperature of about 25° C. and poured onto ice(300 mL). The sulfonyl chloride was extracted into dichloromethane(3×100 mL) dried over sodium sulfate, filtered and concentrated underreduced pressure to provide the title compound as a mixture of isomerswhich were separated by silica gel column eluting with 0-30% ethylacetate:heptanes gradient (1.6 g, 17.7% yield). ¹H NMR (500 MHz,DMSO-d₆) δ ppm 7.97 (1H, d, 6.7 Hz), 7.30 (1H, d, 3.8 Hz), 6.83 (1H, d,3.8 Hz), 3.71-3.82 (1H, m), 0.90 (6H, d, 6.7 Hz). The other isomer(5-[(propan-2-yl)carbamoyl]thiophene-3-sulfonyl chloride) was isolatedfrom this synthesis and used to make the correspondingN-hydroxysulfonamide (2.3 g, 25.5% yield). ¹H NMR (500 MHz, DMSO-d₆) δppm 8.36 (1H, d, 7.8 Hz), 7.91 (1H, d, 1.2 Hz), 7.64 (1H, d, 1.2 Hz),4.01 (1H, sept., 6.8 Hz), 1.13 (6H, d, 6.6 Hz).

5-(Hydroxysulfamoyl)-N-(propan-2-yl)thiophene-2-carboxamide

To a solution of aqueous hydroxylamine (0.99 mL of a 50% solution, 15mmol) in tetrahydrofuran (10 mL) and water (1.6 mL) cooled to −5° C. wasslowly added 5-[(propan-2-yl)carbamoyl]thiophene-2-sulfonyl chloride(1.6 g, 5.98 mmol) portionwise maintaining a reaction temperature ofless than 10° C. The reaction was maintained at this temperature untilcomplete consumption of the sulfonyl chloride was observed by LC-MS(about 10 min), after which time the reaction was diluted with diethylether (30 mL) and the organic portion was separated and washed withwater (10 mL), dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the N-hydroxysulfonamide as a whitesolid (0.7 g, 44% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.86 (1H, br.s.), 9.80 (1H, s), 8.57 (1H, d, 7.8 Hz), 7.81 (1H, d, 4.0 Hz), 7.63 (1H,d, 4.1 Hz), 3.95-4.21 (1H, m), 1.16 (6H, d, 6.6 Hz); predicted[M−H]⁻=263.0160; observed [M−H]⁻=263.0161.

Example 35 N-Hydroxy-5-methanesulfonylthiophene-2-sulfonamide (23)5-Methanesulfonylthiophene-2-sulfonyl chloride

Chlorosulfonic acid (14.4 mL, 215 mmol) was added to2-methanesulfonylthiophene (5.0 g, 30.8 mmol) and the reaction washeated to 90° C. for 1 hour. The resulting colored solution was pouredonto ice and the organic portion extracted into DCM (2×30 mL), driedover sodium sulfate, filtered and concentrated under reduced pressure toprovide the desired sulfonyl chloride as a mixture with the undesired2,4 isomer and the mixture was used directly in the synthesis of thecorresponding N-hydroxysulfonamide (4.6 g, 26% yield). LC-MS t_(R)=1.92min; [M−Cl+OH+H]⁺=240.80; ¹H NMR (250 MHz, DMSO-d₆) δ 7.57 (1H, d, 3.8Hz), 7.18 (1H, d, 3.8 Hz), 3.31 (3H, s).

N-Hydroxy-5-methanesulfonylthiophene-2-sulfonamide

To a solution of aqueous hydroxylamine (1.6 mL of a 50% aqueoussolution, 24 mmol) in THF (10 mL) and water (2 mL) at −10° C. was added5-methanesulfonylthiophene-2-sulfonyl chloride (1.3 g, 4.8 mmol) portionwise maintaining and internal temperature of −5° C. Stirring wascontinued at low temperature until complete consumption of the sulfonylchloride was observed by LC-MS. DCM (20 mL) was added and the reactionwas washed with water (5 mL). The organics were dried over sodiumsulfate, filtered and concentrated under reduced pressure to provide thedesired N-hydroxysulfonamide as a mixture with the undesired 2,4 isomeras an off white solid. Separation of the two isomers was achieved byacidic reverse phase preparative HPLC yielding the desired 2,5-isomer(0.5 g, 41% yield). ¹H NMR (500 MHz, DMSO-d₆) δ 10.09 (2H, s), 7.91 (1H,d, 4.0 Hz), 7.75 (1H, d, 4.0 Hz), 3.48 (s, 3H).

Example 36 N-Hydroxy-2,1,3-benzothiadiazole-4-sulfonamide (24)

To a solution of aqueous hydroxylamine (0.7 mL of a 50% solution, 10.65mmol) in tetrahydrofuran (6 mL) and water (1 mL) cooled to −5° C. wasslowly added 2,1,3-benzothiadiazole-4-sulfonyl chloride (1.0 g, 4.3mmol) maintaining a reaction temperature of less than 10° C. Thereaction was maintained at this temperature until complete consumptionof the sulfonyl chloride was observed by LC-MS (about 5 min), afterwhich time the reaction was diluted with dichloromethane (20 mL) and theorganic portion was separated, washed with water (2×5 mL), dried oversodium sulfate, filtered and concentrated under reduced pressure toprovide the N-hydroxysulfonamide as a yellow solid which was trituratedwith heptane and dried under reduced pressure (0.59 g, 59.9% yield).LC-MS t_(R)=1.26 min, [M−H]⁻=230; ¹H NMR (500 MHz, DMSO-d₆) δ 9.73 (s,2H), 8.45 (dd, J=8.8, 0.9 Hz, 1H), 8.28 (dd, J=7.0, 0.9 Hz, 1H), 7.92(dd, J=8.8, 7.1 Hz, 1H); predicted [M−H]⁻=229.9694; observed[M−H]⁻=229.9687.

Example 37 N-Hydroxy-2-methoxybenzene-1-sulfonamide (25)

To a solution of hydroxylamine HCl (1.31 g, 18.9 mmol) in water (1.6 mL)cooled to 0° C. was added a solution of potassium carbonate (2.62 g,18.9 mmol) in water (2.4 mL) dropwise maintaining an internal reactiontemperature between 5° C. and 15° C. The reaction mixture was stirredfor 15 minutes, whereupon tetrahydrofuran (8 mL) and methanol (2.0 mL)were added. 2-methoxybenzene-1-sulfonyl chloride (1.96 g, 9.48 mmol) wasadded portionwise maintaining a temperature below 15° C. and thereaction mixture was stirred at 5° C. until substantially completeconsumption of the sulfonyl chloride was observed by TLC. The resultingsuspension was concentrated under reduced pressure to remove anyvolatiles and the aqueous suspension was extracted with diethyl ether(2×50 mL). The organic portion was dried over magnesium sulfate,filtered and concentrated under reduced pressure to provide theN-hydroxy sulfonamide as a white solid (0.4 g, 21% yield). ¹H NMR (400MHz, DMSO-d₆) ppm 9.53 (1H, d, J=3.4 Hz), 8.99 (1H, d, J=3.4 Hz), 7.76(1H, dd, J=7.8, 1.7 Hz), 7.62-7.67 (1H, m), 7.23 (1H, d, J=8.3 Hz), 7.11(1H, t, J=7.6 Hz), 3.89 (3H, s); predicted [M−H]⁻=202.0174; observed[M−H]⁻=202.0155.

Example 38 N-Hydroxypyridine-3-sulfonamide (26)

To a solution of aqueous hydroxylamine (11.07 mL of a 50% solution,167.5 mmol) in tetrahydrofuran (40 mL) cooled to −15° C. was slowlyadded a suspension of pyridine-3-sulfonyl chloride (11.9 g, 67 mmol) inTHF (30 mL) and the temperature was remained below 2° C.-3° C.throughout the addition and stirring was continued for an additional 10minutes, after which time LC-MS showed complete consumption of thesulfonyl chloride. Dichloromethane (50 mL) and water (25 mL) were addedand the mixture was shaken, the two layers were separated and theaqueous layer was further extracted with dichloromethane (lx 50 mL). Thecombined organic layers were dried over magnesium sulfate andconcentrated to give a solid which was insoluble in dichloromethane andwas triturated with dichloromethane:heptane (1:1 v:v) to give the titlecompound as a white solid (3.47 g, 29.7% yield). ¹H NMR (500 MHz,DMSO-d₆) δ ppm 9.85 (1H, d, J=2.8 Hz), 9.80 (1H, s), 8.95 (1H, d, J=2.2Hz), 8.87 (1H, dd, J=4.8, 1.5 Hz), 8.20 (1H, dt, J=8.0, 1.9 Hz), 7.69(1H, dd, J=8.0, 4.9 Hz), predicted [M+H]⁺=175.0177; observed[M+H]⁺=175.0172.

Example 39 N-Hydroxy-3,5-dimethyl-1,2-oxazole-4-sulfonamide (27)

To a solution of aqueous hydroxylamine (22.79 mL of a 50% solution, 0.35mol) in tetrahydrofuran (160 mL) and water (27 mL) cooled to −5° C. wasslowly added dimethyl-1,2-oxazole-4-sulfonyl chloride (27 g, 138.02mmol) portionwise maintaining a reaction temperature of less than 10° C.The reaction was maintained at this temperature until completeconsumption of the sulfonyl chloride was observed by LC-MS (about 10min), after which time the reaction was diluted with dichloromethane(250 mL) and the organic portion was separated, washed with water (2×30mL), dried over sodium sulfate, filtered and concentrated under reducedpressure to provide the N-hydroxysulfonamide as a white solid.Trituration was carried out using heptanes to provide the title compoundas a white solid (16.16 g, 60.9% yield). LC-MS t_(R)=1.08 min,[M+H]⁺=193; ¹H NMR (500 MHz, DMSO-d₆) δ 9.79 (d, J=2.8 Hz, 1H), 9.64 (d,J=2.8 Hz, 1H), 2.60 (s, 3H), 2.35 (s, 3H).

Example 40 N-Hydroxy-5-(morpholine-4-carbonyl)thiophene-3-sulfonamide(28) 5-(Morpholine-4-carbonyl)thiophene-3-sulfonyl chloride

To 4-(thiophene-2-carbonyl)morpholine (15 g, 76.04 mmol) was addedchlorosulfonic acid (35.44 g, 304.18 mmol) dropwise at −5 to 0° C. undera nitrogen atmosphere. The temperature was maintained at 0° C. for 30min before stirring at a temperature of about 25° C. for 1 hour. Noreaction was observed and the temperature was increased to 80° C. foranother 12 hours. The resulting slurry was poured onto ice water (500mL) and extracted into dichloromethane (30 mL) before being dried oversodium sulfate and concentrated under reduced pressure to give thecompound as a mixture of isomers. The sulfonyl chloride waschromatographed with a silica gel column eluting with EtOAc:hexane (30%EtOAc) to provide the title compound as a colorless oil (3.0 g, 13.34%yield). LC-MS t_(R)=1.18 min, [M+H]⁺=293; ¹H NMR (400 MHz, CDCl₃) δ 8.35(d, J=1.3 Hz, 1H), 7.62 (d, J=1.4 Hz, 1H), 4.12 (d, J=7.1 Hz, 1H), 3.78(s, 8H), 2.09 (s, 1H), 2.05 (s, 1H), 1.26 (t, J=7.1 Hz, 1H).

Example 41 1-N-Hydroxy-2-N-(propan-2-yl)benzene-1,2-disulfonamide (29)2-Fluoro-N-(propan-2-yl)benzene-1-sulfonamide

A solution of 2-fluorobenzenesulfonyl chloride (3.6 mL, 27.4 mmol) inDCM (50 mL) was cooled at 0° C. and propan-2-amine (3.5 mL, 41.2 mmol)was added followed by pyridine (3.3 mL, 41.2 mmol). The reaction wasleft to warm to a temperature of about 25° C. and stirring was continuedfor 1 hour. The reaction was quenched by the addition of 1M sodiumhydroxide solution (10 mL) and the resulting organic portion was washedwith water (10 mL), 1M aqueous HCl (10 mL) and brine (10 mL) beforebeing dried over magnesium sulfate, filtered and the filtrate wasconcentrated under reduced pressure to give an oil that solidified uponstanding (4.95 g, 83% yield). ¹H NMR (250 MHz, chloroform-d) δ 7.91 (1H,td, 7.6, 1.8 Hz), 7.64-7.48 (1H, m), 7.26 (2H, m), 4.65 (1H, d, 6.5 Hz),3.63-3.40 (1H, m, 6.7 Hz), 1.10 (6H, d, 6.5 Hz).

2-(Benzylsulfanyl)-N-(propan-2-yl)benzene-1-sulfonamide

To a solution of phenylmethanethiol (648 μL, 5.52 mmol) in DMSO (8 mL)was added NaOH (0.28 g, 6.9 mmol) and the reaction was left to stir for20 minutes (until NaOH pellet dissolved).2-Fluoro-N-(propan-2-yl)benzene-1-sulfonamide (645 μL, 4.6 mmol) wasadded and the reaction mixture was heated at 75° C. for 18 hours. Thereaction was allowed to cool to a temperature of about 25° C. and water(1 mL) was added. The reaction was subsequently acidified withconcentrated HCl before extraction of the organic portion into ethylacetate (2×10 mL) The combined organics were washed with water (5 mL)and brine (5 mL) before being dried over magnesium sulfate, filtered andconcentrated under reduced pressure to give an oil which waschromatographed with a silica gel column eluting with a 7-50% ethylacetate:heptanes gradient to provide the desired compound as a yellowoil which solidified on standing and was subsequently triturated withheptanes to provide an off white solid (1.1 g 71% yield). ¹H NMR (250MHz, chloroform-d) δ 8.14-8.00 (1H, m), 7.45-7.23 (8H, m), 5.35 (1H, d,7.2 Hz), 4.24 (2H, s), 3.37 (1H, sept., 6.6 Hz), 0.98 (6H, d, 6.5 Hz)

2-[(Propan-2-yl)sulfamoyl]benzene-1-sulfonyl chloride

A solution of 2-(benzylsulfanyl)-N-(propan-2-yl)benzene-1-sulfonamide(1.5 g, 4.67 mmol) in acetonitrile (46 mL), acetic acid (1.8 mL) andwater (1.2 mL) was cooled at 0° C. (external) and1,3-dichloro-5,5-dimethylimidazolidine-2,4-dione (1.84 g, 9.33 mmol) wasadded in one portion and the reaction was stirred for 1 hour at 0° C.The reaction was diluted with DCM (50 mL) and the organic portion waswashed with aqueous saturated sodium bicarbonate solution (10 mL) andbrine (20 mL) before being dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide a colorless oil which waschromatographed with a silica gel column eluting with a 5-40%heptane:EtOAc gradient to provide the title compound as a white solid(0.8 g, 52% yield). ¹H NMR (250 MHz, chloroform-d) δ 8.36 (2H, dt, 7.9,1.5 Hz), 7.95-7.77 (2H, m), 5.50 (1H, d, 7.3 Hz), 3.66-3.42 (1H, m),1.06 (6H, d, 6.6 Hz).

1-N-Hydroxy-2-N-(propan-2-yl)benzene-1,2-disulfonamide

To a solution of aqueous hydroxylamine (0.8 mL of a 50% solution, 11.7mmol) was added THF (6 mL) and water (1.5 mL) and the solution wascooled to −10° C. To this cold solution was added drop wise a solutionof 2-[(propan-2-yl)sulfamoyl]benzene-1-sulfonyl chloride (1.4 g, 4.7mmol) in THF (3 mL) while the temperature remained below 2-3° C.throughout the addition. The reaction mixture was stirred at 0° C. for10 minutes whereupon LC-MS showed complete consumption of the sulfonylchloride. The reaction was diluted with DCM (10 mL) and was washed withwater (2 mL). The aqueous layer was further extracted into DCM (10 mL)and the organic layers were combined and dried over magnesium sulfate,filtered and concentrated under reduced pressure to give an oil. Thisoil was dissolved in a minimum amount of DCM and then heptane was addedat which time a white solid precipitated. The precipitated solid wascollected by filtration, washed with heptane and dried under reducedpressure to provide1-N-hydroxy-2-N-(propan-2-yl)benzene-1,2-disulfonamide as a white solid(0.6 g, 42% yield). ¹H NMR (250 MHz, DMSO-d₆) δ 10.06 (1H, d, 3.4 Hz),9.09 (1H, d, 3.5 Hz), 8.25-8.08 (2H, m), 8.01-7.78 (2H, m), 7.02 (1H, d,7.5 Hz), 3.41 (1H, dd, 13.5, 6.8 Hz), 0.98 (6H, d, 6.5 Hz).

Example 42 5-Chloro-N-hydroxy-1,3-dimethyl-1H-pyrazole-4-sulfonamide(30)

To a solution of aqueous hydroxylamine (1.4 mL of a 50% solution, 0.02mol) in tetrahydrofuran (12 mL) and water (2 mL) cooled to −5° C. wasslowly added 5-chloro-1,3-dimethyl-1H-pyrazole-4-sulfonyl chloride (2 g,8.7 mmol) maintaining a reaction temperature of less than 10° C. Thereaction was maintained at this temperature until substantially completeconsumption of the sulfonyl chloride was observed by TLC (about 5 min),after which time the reaction was diluted with dichloromethane (20 mL)and the organic portion was separated, washed with water (2×5 mL), driedover sodium sulfate, filtered and concentrated under reduced pressure.The solid was isolated by trituration from heptanes:diethyl ether (1:1v:v) to provide the N-hydroxysulfonamide as a white solid (1.16 g, 58%yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.56 (1H, d, 2.1 Hz), 9.39 (1H,d, 2.3 Hz), 3.77 (3H, s), 2.30 (3H, s), predicted [M−H]⁻=223.9897;observed [M−H]⁻=223.9893.

Example 43 N-Hydroxy-1-methyl-1H-pyrazole-4-sulfonamide (31)

To a solution of aqueous hydroxylamine (0.91 mL of a 50% solution, 13.84mmol) in tetrahydrofuran (3 mL) and water (1 mL) cooled to −5° C. wasslowly added 1-methyl-1H-pyrazole-4-sulfonyl chloride (1 g, 5.54 mmol)maintaining a reaction temperature of less than 10° C. The reaction wasmaintained at this temperature until substantially complete consumptionof the sulfonyl chloride was observed by TLC (about 5 min), after whichtime the reaction was diluted with dichloromethane (10 mL) followed by(200 mL due to low solubility) and the organic portion was separated,washed with water (2×5 mL), dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide the N-hydroxysulfonamideas a white solid (641 mg, 65% yield). LC-MS t_(R)=0.38 min, [M+H]⁺=179;¹H NMR (500 MHz, DMSO-d₆) δ 9.52 (s, 1H), 9.26 (s, 1H), 8.26 (s, 1H),7.72 (s, 1H), 3.89 (s, 3H).

Example 44 N-Hydroxypyridine-2-sulfonamide (32)

A solution of potassium carbonate (6.2 g, 45.0 mmol) in water (4.8 mL)was added drop wise to a solution of hydroxylamine hydrochloride (3.11g, 45.0 mmol) in water (7.2 mL) at 0° C. maintaining an internalreaction temperature between 5° C. and 15° C. Tetrahydrofuran (24 mL)and methanol (6 mL) were added, followed by pyridine-2-sulfonyl chloride(4.0 g, 21.5 mmol) portion wise maintaining a temperature below 15° C.and the reaction mixture was stirred at a temperature of about 25° C.until substantially complete consumption of the sulfonyl chloride wasobserved by TLC. The resulting suspension was concentrated to remove anyvolatiles and the aqueous suspension was diluted with diethyl ether (50mL) and the reaction was washed with water (10 mL). The organics weredried over sodium sulfate, filtered and concentrated under reducedpressure. Recrystallization of the desired compound was achieved fromdiethyl ether provide the expected product as a white solid (1.2 g, 31%yield). ¹H NMR (400 MHz, DMSO-d₆) δ ppm 9.98 (1H, d, 2.9 Hz), 9.60 (1H,d, 2.9 Hz), 8.78 (1H, ddd, 4.6, 1.7, 1.0 Hz), 8.10 (1H, dd, 7.6, 1.7Hz), 8.01 (1H, dt, 7.8, 1.0 Hz), 7.71 (1H, ddd, 7.6, 4.6, 1.2 Hz);predicted [M−H]⁻=173.0021; observed [M−H]⁻=173.0001.

Example 45 3-Bromo-N-hydroxypyridine-2-sulfonamide (33)3-Bromo-2-mercaptopyridine

To a solution of 2-chloro-3-bromopyridine (0.5 g, 2.5 mmol) in ethanol(5 mL) and water (1 mL) in a pressure tube was added sodium hydrogensulfide (0.73 g, 13 mmol). The reaction was heated to 140° C. for 18hours after which time no starting material remained. The product wastaken up in ethyl acetate (10 mL) and was washed with a solution of 10%potassium carbonate solution (5 mL). The resulting aqueous extract wasacidified to pH 5 with 6N hydrochloric acid and extracted with ethylacetate (2×25 mL). The organic phase was died over sodium sulfate,filtered and concentrated under reduced pressure (0.41 g, 84% yield). ¹HNMR (400 MHz, DMSO-d₆) δ ppm 8.05 (1H, dd, 7.5, 1.6 Hz), 7.75 (1H, d,5.1 Hz), 6.66 (1H, dd, 7.6, 6.1 Hz).

3-Bromopyridine-2-sulfonyl chloride

To a solution of 2-mercapto-3-bromo-pyridine (5.3 g, 27.5 mmol) inconcentrated hydrochloric acid (20 mL) cooled to 0° C. was addedchlorine gas at a constant rate until substantially complete saturationwas achieved. Upon reaction completion the sulfonyl chloride was addedto ice water and the resulting aqueous phase extracted withdichloromethane (3×100 mL). The combined organics were dried over sodiumsulfate, filtered and concentrated under reduced pressure. The sulfonylchloride was used directly in the synthesis of the correspondingN-hydroxysulfonamide.

3-Bromo-N-hydroxypyridine-2-sulfonamide

A solution of potassium carbonate (3.21 g, 23.3 mmol) in water (3.6 mL)was added drop wise to a solution of hydroxylamine hydrochloride (1.61g, 23.3 mmol) in water (2.4 mL) at 0° C. maintaining an internalreaction temperature between 5° C. and 15° C. Tetrahydrofuran (12 mL)and methanol (3 mL) were added, followed by 3-bromopyridine-2-sulfonylchloride (3.0 g, 11.65 mmol) portion wise maintaining a temperaturebelow 15° C. and the reaction mixture was stirred at a temperature ofabout 25° C. until substantially complete consumption of the sulfonylchloride was observed by TLC. The resulting suspension was concentratedto remove any volatiles and the aqueous suspension was diluted withdiethyl ether (50 mL) and the reaction was washed with water (10 mL).The aqueous portion was re-extracted with diethyl ether (2×15 mL) andthe combined organics were dried over sodium sulfate, filtered andconcentrated under reduced pressure. The N-hydroxysulfonamide waschromatographed with a silica gel column eluting with a heptanes:ethylacetate gradient to provide the expected product as a white solid (0.4g, 5% yield). ¹H NMR (400 MHz, DMSO-d₆) δ ppm 10.34 (1H, d, 2.9 Hz),9.62 (1H, d, 2.9 Hz), 8.71 (1H, dd, 4.5, 1.3 Hz), 8.37 (1H, dd, 8.2, 1.3Hz), 7.62 (1H, dd, 8.1, 4.4 Hz); predicted [M−H]⁻=250.9126; observed[M−H]⁻=250.9135.

Example 46 4-N-Hydroxythiophene-2,4-disulfonamide (34)

4-N-Hydroxythiophene-2,4-disulfonamide was synthesized from5-sulfamoylthiophene-3-sulfonyl chloride (1 g, 3.8 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamides(0.25 g, 26.5 yield). ¹H NMR (250 MHz, DMSO-d₆) δ 10.05 (s, 2H), 9.99(s, 1H), 9.80 (s, 1H), 8.60 (1H, d, J 1.5 Hz), 7.83 (1H, d, 1.5 Hz).

Example 47 N-Hydroxy-4-(morpholine-4-carbonyl)thiophene-2-sulfonamide(35)

To a solution of aqueous hydroxylamine (0.3 mL of a 50% solution, 4.2mmol) was added THF (3 mL) and water (0.5 mL) and the solution wascooled to −10° C. To this cold solution was added4-(morpholine-4-carbonyl)thiophene-2-sulfonyl chloride (0.5 g, 1.7 mmol)portion wise while the temperature remained below 2-3° C. throughout theaddition. The reaction mixture was stirred at 0° C. for 10 minuteswhereupon LC-MS showed complete consumption of the sulfonyl chloride.The reaction was diluted with DCM (10 mL) and was washed with water (2mL). The aqueous layer was further extracted into DCM (10 mL) and theorganic layers were combined and dried over sodium sulfate, filtered andconcentrated under reduced pressure. The compound was triturated withdiethyl ether to provide the desired compound as a white solid (0.2 g,40% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.88 (1H, d, 2.9 Hz), 9.80(1H, d, 2.9 Hz), 8.22 (1H, s), 7.67 (1H, s), 3.44-3.71 (8H, m);predicted [M−H]⁻=291.0109; observed [M−H]⁻=291.0110.

Example 48N-Hydroxy-5-[5-(trifluoromethyl)-1,2-oxazol-3-yl]thiophene-2-sulfonamide(36)

N-Hydroxy-5-[5-(trifluoromethyl)-1,2-oxazol-3-yl]thiophene-2-sulfonamidewas synthesized from5-[5-(trifluoromethyl)-1,2-oxazol-3-yl]thiophene-2-sulfonyl chloride (1g, 3.2 mmol) according to the herein-described methods for the synthesisof N-hydroxysulfonamides and was triturated from diethyl ether toprovide the desired compound as a white solid (0.7 g, 71% yield). ¹H NMR(500 MHz, DMSO-d₆) δ ppm 9.98 (1H, s), 9.95 (1H, br. s.), 8.17 (1H, s),7.93 (1H, d, 4.0 Hz), 7.78 (1H, d, 3.8 Hz); predicted [M−H]⁻=312.9565;observed [M−H]⁻=312.9564.

Example 496-Chloro-N-hydroxy-7H,7aH-imidazo[2,1-b][1,3]thiazole-5-sulfonamide (37)

6-Chloro-N-hydroxy-7H,7aH-imidazo[2,1-b][1,3]thiazole-5-sulfonamide wassynthesized from 6-chloro-7H,7aH-imidazo[2,1-b][1,3]thiazole-5-sulfonylchloride (0.1 g, 0.4 mmol) according to the herein-described methods forthe synthesis of N-hydroxysulfonamides and was triturated from diethylether to provide the desired compound as a white solid (0.03 g, 30%yield), ¹H NMR (500 MHz, DMSO-d₆) δ ppm 10.02 (1H, br. s.), 9.84 (1H,s), 7.88 (1H, d, 4.6 Hz), 7.61 (1H, d, 4.4 Hz).

Example 50 N-Hydroxy-5-(1,2-oxazol-5-yl)thiophene-2-sulfonamide (38)

N-Hydroxy-5-(1,2-oxazol-5-yl)thiophene-2-sulfonamide was synthesizedfrom 5-(1,2-oxazol-5-yl)thiophene-2-sulfonyl chloride (5.0 g, 20 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was triturated with heptanes to provide thedesired compound as a white solid (2.6 g, 53% yield). ¹H NMR (500 MHz,DMSO-d₆) δ ppm 9.96 (1H, s), 9.92 (1H, br. s.), 8.74 (1H, s), 7.79 (1H,d, 3.8 Hz), 7.7

3 (1H, d, 4.0 Hz), 7.13 (1H, s); predicted [M−H]⁻=244.9691; observed[M−H]⁻=244.9702.

Example 51 4-Fluoro-N-hydroxy-2-methylbenzene-1-sulfonamide (39)

4-Fluoro-N-hydroxy-2-methylbenzene-1-sulfonamide was synthesized from4-fluoro-2-methylbenzene-1-sulfonyl chloride (1.0 g, 4.8 mmol) accordingto the herein-described methods for the synthesis ofN-hydroxysulfonamides and was triturated with heptanes to provide thedesired compound as a white solid (0.65 g, 65% yield). ¹H NMR (500 MHz,DMSO-d₆) δ 9.60 (1H, s), 9.59 (1H, s), 7.89 (1H, dd, 8.7, 6.0 Hz),7.28-7.33 (1H, m), 7.26 (1H, t, 8.5 Hz), 2.60 (3H, s); predicted[M−H]⁻=204.0131; observed [M−H]⁻=204.0138.

Example 52 N-Hydroxy-5-(1,3-oxazol-5-yl)thiophene-2-sulfonamide (40)

N-Hydroxy-5-(1,3-oxazol-5-yl)thiophene-2-sulfonamide was prepared from5-(1,3-oxazol-5-yl)-2-thiophenesulfonyl chloride according to theherein-described methods for the synthesis of N-hydroxysulfonamides(0.02 g, 1%). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.91 (1H, s), 9.82 (1H,br. s.), 8.51 (1H, s), 7.77 (1H, s), 7.66 (1H, d, 3.7 Hz), 7.56 (1H, d,3.5 Hz).

Example 53 N-Hydroxy-2,5-dimethylthiophene-3-sulfonamide (41)

N-Hydroxy-2,5-dimethylthiophene-3-sulfonamide was prepared from2,5-dimethyl-3-thiophenesulfonyl chloride (2.0 g, 9.5 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesand was triturated with heptanes to provide the desired compound as ayellow solid (0.5 g, 25%). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.53 (1H, d,3.1 Hz), 9.39 (1H, d, 3.1 Hz), 6.89 (1H, s), 2.57 (3H, s), 2.38 (3H, s);predicted [M+H]⁺=208.0102; observed [M+H]⁺=208.0374.

Example 54 Methyl 5-(hydroxysulfamoyl)-4-methylthiophene-2-carboxylate(42)

Methyl 5-(hydroxysulfamoyl)-4-methylthiophene-2-carboxylate was preparedfrom methyl 5-(chlorosulfonyl)-4-methyl-2-thiophenecarboxylate (2.0 g,7.9 mmol) according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was triturated with diethyl ether:heptanes toprovide the desired compound as a white solid (0.96 g, 49%). ¹H NMR (500MHz, DMSO-d₆) 9.91 (1H, s), 9.89 (1H, br. s.), 7.74 (1H, s), 3.85 (3H,s), 2.44 (3H, s); predicted [M−H]⁻=249.9844; observed [M−H]⁻=249.9832.

Example 55 5-(Benzenesulfonyl)-N-hydroxythiophene-2-sulfonamide (43)

5-(Benzenesulfonyl)-N-hydroxythiophene-2-sulfonamide was synthesizedfrom 5-(benzenesulfonyl)thiophene-2-sulfonyl chloride (2.5 g, 7.7 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was chromatographed with a silica gel columneluting with a heptanes:ethyl acetate gradient followed by triturationwith heptanes to provide the desired compound as a white solid (1.0 g,40% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 10.12 (1H, d, 2.9 Hz), 10.05(1H, d, 2.9 Hz), 8.06 (2H, d, 8.2 Hz), 7.94 (1H, d, 4.0 Hz), 7.77 (1H,d, 7.3 Hz), 7.64-7.73 (3H, m); predicted [M−H]⁻=317.9565; observed[M−H]⁻=317.9550.

Example 56 N-Hydroxy-5-(1,2-oxazol-3-yl)thiophene-2-sulfonamide (44)

N-Hydroxy-5-(1,2-oxazol-3-yl)thiophene-2-sulfonamide was synthesizedfrom 5-(1,2-oxazol-3-yl)thiophene-2-sulfonyl chloride (0.25 g, 1.0 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides to provide the desired compound as a white solid(0.18 g, 71% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.95 (1H, d, 2.4Hz), 9.91 (1H, d, 2.7 Hz), 8.75 (1H, s), 7.79 (1H, d, 4.0 Hz), 7.73 (1H,d, 3.8 Hz), 7.14 (1H, s); predicted [M−H]⁻=244.9691; observed[M−H]⁻=244.9693.

Example 57 5-Bromo-N-hydroxythiophene-2-sulfonamide (45)

5-Bromo-N-hydroxythiophene-2-sulfonamide was prepared from5-bromothiophene sulfonyl chloride (2.0 g, 7.6 mmol) according to theherein-described methods for the synthesis of N-hydroxysulfonamides andwas triturated from diethyl ether to provide the desired compound as awhite solid (1.2 g, 60%). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.88 (1H, s),9.80 (1H, br. s.), 7.49 (1H, d, 4.0 Hz), 7.40 (1H, d, 3.9 Hz); predicted[M−H]⁻=255.8738; observed [M−H]⁻=255.8727.

Example 58 3,5-Dibromo-N-hydroxythiophene-2-sulfonamide (46)3,5-Dibromothiophene-2-sulfonyl chloride

To a solution of 2,4-dibromothiophene (2.0 g, 8.2 mmol) in DCM (10 mL)cooled to 0° C. was added chlorosulfonic acid (2.9 g, 24 mmol) dropwise. Stirring was continued for an additional 3 hours after which timethe reaction was added to ice and the organic portion extracted into DCM(3×50 mL), dried over sodium sulfate, filtered and concentrated underreduced pressure to provide the desired sulfonyl chloride which was useddirectly in the synthesis of the corresponding N-hydroxysulfonamide (1.8g, 63% yield); ¹H NMR (500 MHz, DMSO-d₆) δ ppm 7.15 (1H, s).

3,5-Dibromo-N-hydroxythiophene-2-sulfonamide

3,5-Dibromo-N-hydroxythiophene-2-sulfonamide was prepared from3,5-dibromothiophene-2-sulfonyl chloride (1.8 g, 5.2 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesand was chromatographed with a silica gel column eluting withheptanes:ethyl acetate (1:1 v:v) followed by trituration from diethylether:heptane to provide the desired compound as a white solid (0.7 g,40% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 10.02 (1H, d, 2.9 Hz), 9.93(1H, d, 2.9 Hz), 7.59 (1H, s); predicted [M−H]⁻=333.7843; observed[M−H]⁻=333.7949.

Example 59 5-Chloro-N-hydroxy-4-nitrothiophene-2-sulfonamide (47)

5-Chloro-N-hydroxy-4-nitrothiophene-2-sulfonamide was prepared from5-chloro-4-nitrothiophene-2-sulfonyl chloride (2.0 g, 7.6 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was chromatographed with a silica gel columneluting with heptanes:ethyl acetate (1:7 v:v) to provide the desiredcompound as an orange solid (0.95 g, 48% yield). ¹H NMR (500 MHz,DMSO-d₆) δ ppm 10.19 (1H, d, 3.6 Hz), 8.05 (1H, s); predicted[M−H]⁻=256.9094; observed [M−H]⁻=256.9087.

Example 60 3-Chloro-N-hydroxythiophene-2-sulfonamide (48) 3Chloro-thiophene-2-sulfonyl chloride

To a solution of 3-chlorothiophene (20 g, 0.17 mol) in DCM (40 mL)cooled to 0° C. was added chlorosulfonic acid (34 mL, 0.51 mol) andstirring was continued for 2 hours; after which time the reactionmixture was poured onto ice and the resulting solution was extractedinto DCM (3×50 mL), dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the desired compound which was useddirectly in the next step (3.5 g, 20%). ¹H NMR (500 MHz, chloroform-d) δppm 7.75 (1H, d, 5.3 Hz), 7.15 (1H, d, 5.3 Hz).

3-Chloro-N-hydroxythiophene-2-sulfonamide

3-Chloro-N-hydroxythiophene-2-sulfonamide was prepared from3-chlorothiophene-2-sulfonyl chloride (3.0 g, 13.8 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesand re-crystallization from 5% ethyl acetate:heptanes to provide thedesired compound as a white solid (1.39 g, 46% yield). ¹H NMR (500 MHz,DMSO-d₆) δ ppm 9.95 (1H, s.), 9.90 (1H, br. s.), 8.16 (1H, d, 5.4 Hz),7.35 (1H, d, 5.2 Hz); predicted [M−H]⁻=211.9243; observed[M−H]⁻=211.9241.

Example 61 N-Hydroxy-2,5-dimethylbenzene-1-sulfonamide (49)

N-Hydroxy-2,5-dimethylbenzene-1-sulfonamide was prepared from2,5-dimethylbenzene-1-sulfonyl chloride (1.0 g, 4.9 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesto provide the desired compound as a white solid (0.6 g, 60% yield). ¹HNMR (250 MHz, DMSO-d₆) δ ppm 9.48-9.54 (2H, m), 7.66 (1H, d, 1.2 Hz),7.34-7.40 (1H, m), 7.25-7.31 (1H, m), 2.54 (3H, s), 2.34 (3H, s);predicted [M−H]⁻=200.0381; observed [M−H]⁻=200.0382.

Example 62 5-Chloro-N-hydroxy-2,1,3-benzoxadiazole-4-sulfonamide (50)

5-Chloro-N-hydroxy-2,1,3-benzoxadiazole-4-sulfonamide was prepared from5-chloro-2,1,3-benzoxadiazole-4-sulfonyl chloride (1 g, 3.9 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was chromatographed with a silica gel columneluting with heptanes:ethyl acetate (1:1 v:v) to provide the desiredcompound as an off white solid (0.04 g, 5% yield). ¹H NMR (250 MHz,DMSO-d₆) δ ppm 10.19 (1H, d, 2.9 Hz), 9.95 (1H, d, 2.9 Hz), 8.45 (1H, d,9.4 Hz), 7.82 (1H, d, 9.4 Hz).

Example 63 4-(Benzenesulfonyl)-N-hydroxythiophene-2-sulfonamide (51)

4-(Benzenesulfonyl)-N-hydroxythiophene-2-sulfonamide was prepared from4-(benzenesulfonyl)thiophene-2-sulfonyl chloride (1.0 g, 3.1 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was chromatographed with a silica gel columneluting with 30% ethyl acetate:heptanes to provide the desired compoundas an off white solid (0.51 g, 51% yield). ¹H NMR (250 MHz, DMSO-d₆) δppm 10.05 (1H, br. s), 9.44 (1H, s), 8.84 (1H, s), 8.09 (1H, m,),8.00(1H, m,), 7.87 (1H, m,), 7.71 (3H, m,); predicted [M−H]⁻=317.9565;observed [M−H]⁻=317.9602.

Example 64 N-Hydroxy-3,4-dimethoxybenzene-1-sulfonamide (52)

N-Hydroxy-3,4-dimethoxybenzene-1-sulfonamide was synthesized from3,4-dimethoxybenzene-1-sulfonyl chloride (2 g, 8.46 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesand was triturated with diethyl ether:heptanes (0.3 g, 15% yield). ¹HNMR (500 MHz, DMSO-d₆) δ ppm 9.48 (1H, d, 3.5 Hz), 9.40 (1H, d, 3.5 Hz),7.42 (1H, dd, 8.4 Hz, 2.1 Hz),7.33 (1H, d, 2.0 Hz), 7.16 (1H, d, 8.5Hz), 3.85 (1H, s), 3.81 (1H, s,); predicted [M−H]⁻=232.028; observed[M−H]⁻=232.0285.

Example 65 N-Hydroxy-2,3,5,6-tetramethylbenzene-1-sulfonamide (53)

N-Hydroxy-2,3,5,6-tetramethylbenzene-1-sulfonamide was prepared from2,3,5,6-tetramethylbenzene-1-sulfonyl chloride (2 g, 8.6 mmol) accordingto the herein-described methods for the synthesis ofN-hydroxysulfonamides to provide the desired compound as a white solid(0.7 g, 34% yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 9.52 (1H, br. s),9.36 (1H, s), 7.30 (1H, s), 2.50 (6H, s), 2.27 (6H, s); predicted[M−H]⁻=228.0694; observed [M−H]⁻=228.074.

Example 66 N-Hydroxy-3,5-bis(trifluoromethyl)benzene-1-sulfonamide (54)

N-Hydroxy-3,5-bis(trifluoromethyl)benzene-1-sulfonamide was preparedfrom 3,5-bis(trifluoromethyl)benzene-1-sulfonyl chloride according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesand was triturated with diethyl ether:heptane to provide the desiredcompound as a white solid (0.48 g, 24% yield). ¹H NMR (250 MHz, DMSO-d₆)δ ppm 9.99 (2H, s), 8.58 (1H, s), 8.37 (2H, s); predicted[M−H]⁻=307.9816; observed [M−H]⁻=307.9823.

Example 67 Methyl 4-chloro-3-(hydroxysulfamoyl)benzoate (55) Methyl4-chloro-3-(chlorosulfonyl)benzoate

To 4-chloro-3-(chlorosulfonyl)benzoyl chloride (2 g, 7.3 mmol) was addedMeOH (20 mL) with stirring. After 10 minutes the reaction wasconcentrated under reduced pressure and used directly in the synthesisof the corresponding N-hydroxysulfonamide (1.9 g, 96% yield). ¹H NMR(500 MHz, chloroform-d) δ 8.79 (1H, d, J2.0 Hz), 8.30 (1H, dd, 8.3, 2.0Hz), 7.74 (1H, d, 8.3 Hz), 3.99 (3H, s).

Methyl 4-chloro-3-(hydroxysulfamoyl)benzoate

Methyl 4-chloro-3-(hydroxysulfamoyl)benzoate was synthesized from methyl4-chloro-3-(chlorosulfonyl)benzoate (0.7 g, 2.6 mmol) according to theherein-described methods for the synthesis of N-hydroxysulfonamides (0.3g, 45% yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 10.05 (1H, br. s.), 9.90(1H, s), 8.50 (1H, d, 2.1 Hz), 8.18 (1H, dd, 8.4, 2.1 Hz), 7.85 (1H, d,8.2 Hz), 3.90 (3H, s); predicted [M−H]⁻=263.9733; observed[M−H]⁻=263.973.

Example 68 2-Fluoro-N-hydroxy-5-methylbenzene-1-sulfonamide (56)

2-Fluoro-N-hydroxy-5-methylbenzene-1-sulfonamide was prepared from2-fluoro-5-methylbenzene-1-sulfonyl chloride (1 g, 4.8 mmol) accordingto the herein-described methods for the synthesis ofN-hydroxysulfonamides (0.19 g, 20% yield). ¹H NMR (500 MHz, DMSO-d₆) δppm 9.71 (2H, s), 7.61 (1H, dd, 6.6, 1.7 Hz), 7.54 (1H, dt, 8.2, 2.3Hz), 7.33 (1H, dd, 10.0, 8.6 Hz), 2.36 (3H, s); predicted[M−H]⁻=204.0131; observed [M−H]⁻=204.0121.

Example 69 4-Chloro-N-(3-chloropropyl)-3-(hydroxysulfamoyl)-benzamide(57) 2-Chloro-5-[(3-chloropropyl)carbamoyl]benzene-1-sulfonyl chloride

To a solution of 4-chloro-3-(chlorosulfonyl)benzoyl chloride (1.5 g,5.51 mmol) in chlorobenzene (20 mL) was added azetidine hydrochloride(0.54 g, 5.79 mmol) and the reaction was heated to 130° C. for 18 hoursafter which time LC-MS showed no starting material remaining. Thereaction mixture was concentrated under reduced pressure and trituratedusing diethyl ether to provide the desired product as an off white solidwhich was used directly in the synthesis of the correspondingN-hydroxysulfonamide (1 g, 55% yield).

4-Chloro-N-(3-chloropropyl)-3-(hydroxysulfamoyl)-benzamide

4-Chloro-N-(3-chloropropyl)-3-(hydroxysulfamoyl)-benzamide was preparedfrom 2-chloro-5-[(3-chloropropyl)carbamoyl]benzene-1-sulfonyl chloride(1 g, 3.4 mmol) according to the herein-described methods for thesynthesis of N-hydroxysulfonamides and was triturated with diethyl etherto provide the desired compound as a white solid (0.13 g, 14% yield). ¹HNMR (500 MHz, DMSO-d₆) δ ppm 9.88 (1H, d, 2.7 Hz), 9.81 (1H, d, 2.9 Hz),8.86 (1H, t, 5.4 Hz), 8.45 (1H, d, 2.0 Hz), 8.11 (1H, dd, 8.4, 2.0 Hz),7.81 (1H, d, 8.4 Hz), 3.70 (2H, t, 6.5 Hz), 3.40 (2H, q, 6.5 Hz),1.91-2.06 (2H, m).

Example 702-Chloro-N-hydroxy-5-[4-(hydroxyimino)piperidine-1-carbonyl]benzene-1-sulfonamide(58) 2-Chloro-5-(4-oxopiperidine-1-carbonyl)benzene-1-sulfonyl chloride

To a solution of 4-chloro-3-(chlorosulfonyl)benzoyl chloride (1.0 g, 3.7mmol) in chlorobenzene (15 mL) was added 4-piperidinone hydrochloride(0.59 g, 3.9 mmol) and the reaction was heated to 130° C. for 18 hoursafter which time LC-MS showed no starting material remaining. Thereaction mixture was concentrated under reduced pressure and taken up inDCM (50 mL), washed with water (2×10 mL) before being dried overmagnesium sulfate, filtered and concentrated under reduced pressure toprovide the product which was triturated with diethyl ether to providethe desired compound as a off white solid (0.27 g, 22% yield). ¹H NMR(500 MHz, DMSO-d₆) δ ppm 7.96 (1H, d, 1.6 Hz), 7.51-7.40 (2H, m),3.74-3.56 (4H, m) 2.55-2.27 (4H, m).

2-Chloro-N-hydroxy-5-[4-(hydroxyimino)piperidine-1-carbonyl]benzene-1-sulfonamide

2-Chloro-N-hydroxy-5-[4-(hydroxyimino)piperidine-1-carbonyl]benzene-1-sulfonamidewas synthesized from2-chloro-5-(4-oxopiperidine-1-carbonyl)benzene-1-sulfonyl chloride (0.27g, 0.82 mmol) according to the herein-described methods for thesynthesis of N-hydroxysulfonamides and was triturated withheptanes:diethyl ether to provide the desired compound as a white solid(0.05 g, 16% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.98 (1H, m), 9.86(1H, m), 7.95 (1H, m), 7.71 (2H, m), 3.59 (2H, m), 3.29 (2H, m), 3.16(2H, m), 2.95 (2H, m).

Example 714-Chloro-3-(hydroxysulfamoyl)-N-(2-methoxyethyl)-N-methylbenzamide (59)2-Chloro-5-[(2-methoxyethyl)(methyl)carbamoyl]benzene-1-sulfonylchloride

To a solution of 4-chloro-3-(chlorosulfonyl)benzoyl chloride (2.0 g, 3.7mmol) in chlorobenzene (25 mL) was added 2-(methoxyethyl)methylaminehydrochloride (0.48 g, 3.9 mmol) and the reaction was heated to 130° C.for 18 hours after which time LC-MS showed no starting materialremaining. The reaction mixture was concentrated under reduced pressureand used directly in the synthesis of the correspondingN-hydroxysulfonamide (2 g, 75% yield).

4-Chloro-3-(hydroxysulfamoyl)-N-(2-methoxyethyl)-N-methylbenzamide

4-Chloro-3-(hydroxysulfamoyl)-N-(2-methoxyethyl)-N-methylbenzamide wassynthesized from2-chloro-5-[(2-methoxyethyl)(methyl)carbamoyl]benzene-1-sulfonylchloride (2 g, 6.1 mmol) according to the herein-described methods forthe synthesis of N-hydroxysulfonamides and was triturated with diethylether followed by silica gel column eluting with ethyl acetate:heptanes(1:1 v:v) to provide the desired compound as an off white solid (0.17 g,9% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.98 (1H, m), 9.86 (1H, m),7.95 (1H, m), 7.71 (2H, m), 3.59 (2H, m), 3.29 (2H, m), 3.16 (2H, m),2.95 (3H, m).

Example 72 2-Hydroxy-5-(hydroxysulfamoyl)benzoic acid (60)

2-Hydroxy-5-(hydroxysulfamoyl)benzoic acid was prepared from5-(chlorosulfonyl)-2-hydroxybenzoic acid (1 g, 4.2 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesand was isolated as a white solid (0.4 g, 41% yield). ¹H NMR (500 MHz,DMSO-d₆) δ ppm 10.75 (1H, br. s.), 10.66 (1H, s), 9.39 (1H, d, 2.1 Hz),9.04 (1H, dd, 8.8, 2.2 Hz), 8.31 (1H, d, 5.0 Hz); predicted[M−H]⁻=231.9916; observed [M−H]⁻=231.9907.

Example 73N-Hydroxy-4-methyl-3,4-dihydro-2H-1,4-benzoxazine-7-sulfonamide (61)

N-Hydroxy-4-methyl-3,4-dihydro-2H-1,4-benzoxazine-7-sulfonamide wasprepared from 4-methyl-3,4-dihydro-2H-1,4-benzoxazine-7-sulfonylchloride (0.9 g, 3.8 mmol) according to the herein-described methods forthe synthesis of N-hydroxysulfonamides and was triturated withheptanes:ethyl acetate to provide the desired product as an off whitesolid (0.35 g, 38% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.40 (1H, br.s.), 9.32 (1H, s), 7.00-7.12 (2H, m), 6.83 (1H, d, 8.9 Hz), 4.20-4.36(2H, m), 3.24-3.35 (2H, m), 2.87 (3H, s); predicted [M+H]⁺=245.0595;observed [M+H]⁺=245.0589.

Example 74 2-Chloro-N,4-dihydroxybenzene-1-sulfonamide (62)2-Chloro-4-hydroxybenzene-1-sulfonyl chloride

To a solution of 2-chloro-4-hydroxyaniline (5.0 g, 35 mmol) in aceticacid (30 mL) and HCl (7 mL) cooled to 0° C. was added sodium nitrite(2.65 g, 38.5 mmol) portion wise maintaining an internal temperature <5°C. The reaction mixture was allowed to stir at 0° C. for 1 hour.Simultaneously, CuCl₂.H₂O (5.98 g, 34.8 mmol) was suspended inAcOH:water (20 mL:10 mL) at 0° C. and stirred at 0° C. until all CuCl₂was in solution. SO₂ gas was condensed into a flask at −78° C. via theaid of a cold finger and the diazo compound and CuCl₂ solution added andthe reaction warmed to 0° C. The reaction was allowed to warm to atemperature of about 25° C. over 18 hours and was quenched by additionto ice and extracted into diethyl ether (3×100 mL). The organics weredried over sodium sulfate, filtered and concentrated under reducedpressure to provide the title compound as a yellow oil which was useddirectly in the next step.

2-Chloro-N,4-dihydroxybenzene-1-sulfonamide

2-Chloro-N,4-dihydroxybenzene-1-sulfonamide was prepared from2-chloro-4-hydroxybenzene-1-sulfonyl chloride according to theherein-described methods for the synthesis of N-hydroxysulfonamides andwas chromatographed with a silica gel column eluting with 1% MeOH:DCM toprovide the desired compound as a white solid (0.3 g, 15% yield). ¹H NMR(250 MHz, DMSO-d₆) δ ppm 10.93 (1H, s), 9.58 (1H, d, 3.0 Hz), 9.42 (1H,d, 3.0 Hz), 7.80 (1H, d, 8.7 Hz), 6.97 (1H, d, 2.4 Hz), 6.89 (1H, dd,8.7, 2.4 Hz) predicted [M−H]⁻=221.9628; observed [M−H]⁻=221.9621.

Example 75 3,5-Dichloro-N,4-dihydroxybenzene-1-sulfonamide (63)

3,5-Dichloro-N,4-dihydroxybenzene-1-sulfonamide was prepared from3,5-dichloro-4-hydroxybenzene-1-sulfonyl chloride (1 g, 3.8 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides to provide the desired compound as a white solid(0.05 g, 5% yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 9.60 (1H, br. s.),9.43 (1H, s), 7.64 (2H, s).

Example 76 4-Chloro-2-hydroxy-5-(hydroxysulfamoyl)-N,N-dimethylbenzamide(64) 2-Chloro-5-(dimethylcarbamoyl)-4-hydroxybenzene-1-sulfonyl chloride

To a solution of 5-(chlorosulfonyl)-2-hydroxybenzoic acid (1 g, 4.2mmol) in toluene (20 mL) was added thionyl chloride (0.62 mL, 8.4 mmol)and the reaction was heated to reflux for 1 hour or until no furtherstarting material was evident by TLC. The reaction was concentratedunder reduced pressure and used directly in the synthesis of the amide(1 g, 82% yield). To a solution of4-chloro-5-(chlorosulfonyl)-2-hydroxybenzoyl chloride (1 g, 3.5 mmol) inchlorobenzene (25 mL) was added dimethylamine hydrochloride (0.31 g, 3.9mmol) and the reaction was heated to 130° C. for 18 hours after whichtime LC-MS showed no starting material remaining. The reaction mixturewas concentrated under reduced pressure and used directly in thesynthesis of the corresponding N-hydroxysulfonamide (2.9 g, quantitativeyield); LC-MS t_(R)=1.75 min, [M+H]⁺=264.

4-Chloro-2-hydroxy-5-(hydroxysulfamoyl)-N,N-dimethylbenzamide

4-Chloro-2-hydroxy-5-(hydroxysulfamoyl)-N,N-dimethylbenzamide wasprepared from 2-Chloro-5-(dimethylcarbamoyl)-4-hydroxybenzene-1-sulfonylchloride (2.9 g, 9.7 mmol) according to the herein-described methods forthe synthesis of N-hydroxysulfonamides and was chromatographed with asilica gel column eluting with 10% MeOH in DCM followed by triturationfrom DCM to provide the desired compound as an off white solid (0.38 g,13% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 11.42 (1H, br. s.), 9.67(1H, d, 2.7 Hz), 9.60 (1H, d, 2.9 Hz), 7.68 (1H, s), 7.06 (1H, s), 2.96(3H, br. s.), 2.81 (3H, br. s.); predicted [M−H]⁻=292.9999; observed[M−H]⁻=293.0003.

Example 775-Chloro-N-hydroxy-1-methyl-2,3-dihydro-1H-indole-6-sulfonamide (65)5-Chloro-1-methyl-2,3-dihydro-1H-indole

To a solution of 5-chloro-2,3-dihydro-1H-indole (3.0 g, 19.5 mmol) inDMF (60 mL) was added dimethylcarbonate (5.27 g, 58.6 mmol) andpotassium carbonate (1.35 g, 9.75 mmol). The reaction was heated toreflux for 18 hours, after which time no starting material was evidentby LC-MS. The reaction mixture was allowed to cool to a temperature ofabout 25° C. and the product isolated by extraction into diethyl ether(250 mL). The organic portion was washed with water (2×100 mL) and theorganics dried over magnesium sulfate, filtered and concentrated underreduced pressure to provide the title compound as a white solid (2.4 g,71% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 7.67 (1H, br. s.), 7.27 (1H,s), 7.20 (1H, d, 8.7 Hz), 3.97 (2H, t, 8.7 Hz), 3.74 (3H, br. s.), 3.09(2H, t, 8.7 Hz).

5-Chloro-1-methyl-2,3-dihydro-1H-indole-6-sulfonyl chloride

5-Chloro-1-methyl-2,3-dihydro-1H-indole (0.6 g, 3.6 mmol) andchlorosulfonic acid (1.7 g, 14.3 mmol) were heated in a sealed tube to70° C. for 18 hours. The reaction was quenched by pouring onto ice andthe resulting solid was dried under reduced pressure thenchromatographed with silica gel column eluting with 20% heptane:ethylacetate to provide the title compound as a white solid (0.37 g, 38%yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 8.23 (1H, br. s.), 7.19 (1H, s),3.97 (2H, t, 8.7 Hz), 3.75 (3H, s), 3.07 (2H, t, 8.6 Hz).

5-Chloro-N-hydroxy-1-methyl-2,3-dihydro-1H-indole-6-sulfonamide

5-Chloro-N-hydroxy-1-methyl-2,3-dihydro-1H-indole-6-sulfonamide wasprepared from 5-chloro-1-methyl-2,3-dihydro-1H-indole-6-sulfonylchloride (0.35 g, 1.3 mmol) according to the herein-described methodsfor the synthesis of N-hydroxysulfonamides (0.19 g, 55% yield). ¹H NMR(250 MHz, DMSO-d₆) δ ppm 9.54-9.72 (2H, m), 8.33 (1H, br. s.), 7.51 (1H,s), 4.03 (2H, t, 8.8 Hz), 3.76 (3H, s), 3.18 (2H, t, 8.5 Hz).

Example 78 2-Chloro-N,5-dihydroxybenzene-1-sulfonamide (66)

2-Chloro-N,5-dihydroxybenzene-1-sulfonamide was prepared from2-chloro-5-hydroxy benzene-1-sulfonyl chloride (2.32 g, 10 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was chromatographed with a neutral reversephase preparative HPLC to provide the desired compound as a white solid(0.05 g, 3% yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 9.74 (2H, s),7.31-7.53 (2H, m), 7.04 (1H, d, 8.7, 2.9 Hz).

Example 795-Bromo-N-hydroxy-1-methyl-2,3-dihydro-1H-indole-6-sulfonamide (67)

5-Bromo-1-methyl-2,3-dihydro-1H-indole5-Bromo-1-methyl-2,3-dihydro-1H-indole was synthesized using the methoddescribed for the synthesis of 5-chloro-1-methyl-2,3-dihydro-1H-indole(1.1 g, 54% yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 7.60 (1H, br. s.),7.40 (1H, d, 0.9 Hz), 7.28-7.37 (1H, m), 3.96 (2H, t, 8.7 Hz), 3.74 (3H,s), 3.10 (2H, t, 8.7 Hz).

5-Bromo-1-methyl-2,3-dihydro-1H-indole-6-sulfonyl chloride

5-Bromo-1-methyl-2,3-dihydro-1H-indole-6-sulfonyl chloride wassynthesized using the method described for the synthesis of5-chloro-1-methyl-2,3-dihydro-1H-indole-6-sulfonyl chloride (0.29 g, 34%yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 8.30 (1H, br. s.), 7.37 (1H, s),3.96 (2H, t, 8.7 Hz), 3.74 (3H, br. s.), 3.07 (2H, t, 8.7 Hz).

5-Bromo-N-hydroxy-1-methyl-2,3-dihydro-1H-indole-6-sulfonamide

5-Bromo-N-hydroxy-1-methyl-2,3-dihydro-1H-indole-6-sulfonamide wasprepared from bromo-1-methyl-2,3-dihydro-1H-indole-6-sulfonylchloride(0.29 g, 0.94 mmol) according to the herein-described methodsfor the synthesis of N-hydroxysulfonamides (0.24 g, 82% yield). ¹H NMR(250 MHz, DMSO-d₆) δ ppm 9.54-9.74 (2H, m), 8.38 (1H, br. s.), 7.68 (1H,s), 4.02 (2H, t, 8.7 Hz), 3.76 (3H, s), 3.18 (2H, t, 8.6 Hz).

Example 80 2-Chloro-N-hydroxy-5-(methoxymethyl)benzene-1-sulfonamide(68) 1-Chloro-4-(methoxymethyl)-2-nitrobenzene

1-Chloro-4-(methoxymethyl)-2-nitrobenzene was synthesized according tothe method detailed in Buenzli et al., J. Amer. Chem. Soc.120:12274-12288 (1998). To a solution of KOH (5.98 g, 106 mmol) in DMSO(50 mL) was added 4-chloro-3-nitrobenzyl alcohol (5.0 g, 26.6 mmol) andmethyl iodide (4 mL, 64 mmol). Stirring was continued for 1 hour afterwhich time water (60 mL) was added and the reaction was extracted intoDCM (3×50 mL), washed with water and dried over sodium sulfate, filteredand concentrated under reduced pressure (4.7 g, 88% yield). ¹H NMR (250MHz, chloroform-d) δ ppm 7.86 (1H, d, 1.4 Hz), 7.40-7.61 (2H, m), 4.49(2H, s), 3.44 (3H, s).

2-Chloro-5-(methoxymethyl)benzene-1-sulfonyl chloride

To a solution of 1-chloro-4-(methoxymethyl)-2-nitrobenzene (2.7 g, 13.4mmol) in EtOH (14 mL) and water (2 mL) was added iron (1.94 g, 34.8mmol) and HCl (5 drops). The reaction was heated to 80° C. for 1 hour.The cooled reaction mixture was filtered through CELITE, washed withEtOAc (50 mL) and concentrated under reduced pressure and used directlyin the next step. To a solution of 2-chloro-5-(methoxymethyl)aniline(4.19 g, 24.5 mmol) in acetic acid (25 mL) and HCl (6 mL) cooled to 0°C. was added sodium nitrite (1.85 g, 26.9 mmol) portion wise maintainingan internal temperature <5° C. The reaction mixture was allowed to stirat 0° C. for 1 hour. Simultaneously, CuCl₂.H₂O (4.16 g, 24.5 mmol) wassuspended in AcOH:water (25 mL:10 mL) at 0° C. and stirred at 0° C.until all CuCl₂ was in solution. SO₂ gas was condensed into a flask at−78° C. via the aid of a cold finger and the diazo compound and CuCl₂solution added and the reaction warmed to 0° C. The reaction was allowedto warm to a temperature of about 25° C. over 2 hours. The reaction wasquenched by addition to ice and extracted into DCM (3×50 mL). Theorganics were dried over sodium sulfate, filtered and concentrated underreduced pressure to provide the title compound as a yellow oil (5.1 g,81% yield). ¹H NMR (250 MHz, DMSO-d₆) δ ppm 7.82 (1H, d, 2.0 Hz),7.30-7.48 (2H, m), 4.38 (2H, s), 3.27 (3H, s).

2-Chloro-N-hydroxy-5-(methoxymethyl)benzene-1-sulfonamide

1-Chloro-4-(methoxymethyl)-2-nitrobenzene was prepared from2-chloro-5-(methoxymethyl) benzene-1-sulfonyl chloride (1 g, 3.9 mmol)according to herein-described methods for the synthesis ofN-hydroxysulfonamides (0.55 g, 56% yield). ¹H NMR (250 MHz, DMSO-d₆) δppm 9.69-9.89 (2H, m), 7.93 (1H, d, 1.7 Hz), 7.68 (1H, d, 8.1 Hz), 7.60(1H, dd, 8.2, 2.0 Hz), 4.49 (2H, s), 3.33 (3H, s); predicted[M−H]⁻=249.9941; observed [M−H]⁻=249.9945.

Example 81 Methyl 5-(hydroxysulfamoyl)furan-2-carboxylate (69)

Methyl 5-(hydroxysulfamoyl)furan-2-carboxylate was prepared from methyl5-(chlorosulfonyl)furan-2-carboxylate (1.0 g, 4.5 mmol) according to theherein-described methods for the synthesis of N-hydroxysulfonamides andwas chromatographed with a silica gel column eluting with heptanes:ethylacetate (4:1 v:v) followed by trituration from heptane to provide thedesired compound as a yellow solid (0.46 g, 47% yield). ¹H NMR (500 MHz,DMSO-d₆) δ ppm 10.28 (1H, d, 2.8 Hz), 9.89 (1H, d, 2.8 Hz), 7.48 (1H, d,3.8 Hz), 7.36 (1H, d, 3.6 Hz), 3.87 (3H, s).

Example 82 N-Hydroxy-2,5-dimethylfuran-3-sulfonamide (70)

N-Hydroxy-2,5-dimethylfuran-3-sulfonamide was prepared from2,5-dimethylfuran-3-sulfonyl chloride (0.5 g, 2.6 mmol) according to theherein-described methods for the synthesis of N-hydroxysulfonamides andwas triturated with DCM:heptane to provide the desired compound as awhite solid (0.34 g, 69% yield). ¹H NMR (CDCl₃, 500 MHz) δ ppm 6.65 (1H,d, 3.7 Hz), 6.20 (1H, s), 6.13 (1H, s), 2.54 (3H, s), 2.28 (3H, s).

Example 83N-Hydroxy-8-oxatricyclo[7.4.0.0]trideca-1(9),2(7),3,5,10,12-hexaene-4-sulfonamide(71)

N-Hydroxy-8-oxatricyclo[7.4.0.0]trideca-1(9),2(7),3,5,10,12-hexaene-4-sulfonamidewas synthesized from8-oxatricyclo[7.4.0.0^(2,7)]trideca-1(9),2,4,6,10,12-hexaene-4-sulfonylchloride (1.0 g, 3.75 mmol) according to the herein-described methodsfor the synthesis of N-hydroxysulfonamides and was triturated withdiethyl ether to provide the desired compound as a white solid (0.46 g,48% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.66 (1H, d, 3.3 Hz), 9.62(1H, d, 3.3 Hz), 8.67 (1H, d, 1.7 Hz), 8.35 (1H, d, 7.7 Hz), 7.93-8.02(2H, m), 7.80 (1H, d, 8.4 Hz), 7.58-7.65 (1H, m), 7.49 (1H, t, 7.5 Hz).

Example 84 2-(Ethanesulfonyl)-N-hydroxybenzene-1-sulfonamide (72)1-Chloro-2-(ethylsulfanyl)benzene

To a solution of sodium methoxide (5.6 g, 103.7 mmol) in MeOH (100 mL)was added 2-chlorobenzene-1-thiol (10.0 g, 69.1 mmol) in MeOH (50 mL).The reaction was cooled to 0° C. and a solution of iodoethane (5.8 mL,72.6 mmol) in MeOH (50 mL) was added dropwise. The reaction was stirredfor 18 hours at a temperature of about 25° C. where upon LC-MS showed nostarting material present. The solvent was removed and the reactionquenched by the addition of water (100 mL). The organics were extractedinto DCM (3×200 mL), combined, dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide the desired compound as aclear oil (11.5 g, 96% yield). ¹H NMR (CDCl₃, 500 MHz) δ ppm 7.36 (1H,dd, 7.9, 1.2 Hz), 7.28-7.19 (2H, m), 7.13-7.07 (1H, m), 2.97 (2H, q, 7.4Hz), 1.37 (3H, t, 7.4 Hz).

1-Chloro-2-(ethanesulfonyl)benzene

A solution of 1-chloro-2-(ethylsulfanyl)benzene (11.5 g, 66.6 mmol) inDCM (230 mL) was added over 1 hour to a 0-5° C. solution of 10% sulfuricacid (345 mL) with simultaneous addition of potassium permanganate solid(35.8 g, 0.23 mol) in portions. The resulting reaction mixture wasallowed to warm to a temperature of about 25° C. and stirring wascontinued for 1 hour, after which time LC-MS showed the reaction to becomplete. Sodium bisulfite (65 g) was added to the reaction mixtureslowly until all color had disappeared from the reaction and a clear,colorless solution was observed and the organic phase separated. Theaqueous phase was re-extracted into DCM (3×100 mL) and the combinedorganic portion was dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the desired compound as a clear,colorless oil which was used directly in the next step (14.0 g, 99.99%yield). ¹H NMR (CDCl₃, 500 MHz) δ ppm 8.13 (1H, dd, 8.0, 1.1 Hz),7.62-7.54 (2H, m), 7.48 (1H, ddd, 8.6, 6.6, 2.1 Hz), 3.44 (2H, q, 7.5Hz), 1.27 (3H, t, 7.5 Hz).

1-(Benzylsulfanyl)-2-(ethanesulfonyl)benzene

To a solution of 1-chloro-2-(ethanesulfonyl)benzene (14.0 g, 68.4 mmol)in DMSO (70 mL) was added (benzylsulfanyl)methanimidamide HCl (14.56 g,71.8 mmol) was added and the reaction mixture was cooled to 10° C. NaOH(6.84 g, 171.0 mmol) was added to the reaction mixture and the reactionwas heated to 75° C. for 18 hours and allowed to cool to a temperatureof about 25° C. where stirring was continued for an additional 72 hours.The reaction was quenched by the addition of water (50 mL) and theresulting aqueous solution extracted into DCM (4×100 mL). The combinedorganics were washed with brine solution (50 mL), dried over sodiumsulfate, filtered and concentrated under reduced pressure to provide theproduct as a yellow oil which was chromatographed with a silica gelcolumn eluting with 50-100% DCM acetate:heptanes gradient to provide thedesired compound as a yellow oil (3.25 g, 16% yield). ¹H NMR (CDCl₃, 500MHz) δ ppm 8.06-8.00 (1H, m), 7.54-7.45 (2H, m), 7.35 (1H, ddd, 8.5,6.8, 1.9 Hz), 7.32-7.21 (5H, m), 4.23 (2H, s), 3.37 (2H, d, 7.4 Hz),1.11 (3H, t, 7.4 Hz).

2-(Ethanesulfonyl)benzene-1-sulfonyl chloride

Chlorine gas was bubbled through a solution of1-(benzylsulfanyl)-2-(ethanesulfonyl)benzene (3.25 g, 11.1 mmol) inacetic acid (110 mL) and water (10 mL) maintaining an internaltemperature of <10° C. for 1 hour. Upon complete addition of thechlorine gas the sulfonyl chloride was extracted into DCM (100 mL) andwas washed with water (100 mL) and 2.5% w:v NaOH solution (50 mL). Theorganic portion was dried over sodium sulfate, filtered and concentratedunder reduced pressure. The resulting solid was triturated with heptanesto provide the desired compound as a white solid (2.7 g, 89% yield). ¹HNMR (CDCl₃, 500 MHz) δ ppm 8.44 (1H, dd, 7.8, 1.3 Hz), 8.40 (1H, dd,7.7, 1.4 Hz), 7.97 (2H, dtd, 22.4, 7.6, 1.3 Hz), 3.61 (2H, q, 7.5 Hz),1.36 (3H, t, 7.5 Hz).

2-(Ethanesulfonyl)-N-hydroxybenzene-1-sulfonamide

2-(Ethanesulfonyl)-N-hydroxybenzene-1-sulfonamide was synthesized from2-(ethanesulfonyl)benzene-1-sulfonyl chloride (1.0 g, 3.7 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was triturated with heptanes to provide thedesired compound as a white solid (0.8 g, 83% yield). ¹H NMR (DMSO, 500MHz) δ ppm 10.12 (1H, d, 3.5 Hz), 8.96 (1H, d, 3.5 Hz), 8.26-8.19 (2H,m), 8.08-7.99 (2H, m), 3.65 (2H, q, 7.4 Hz), 1.17 (3H, t, 7.4 Hz).

Example 85 N-Hydroxy-2-(propane-2-sulfonyl)benzene-1-sulfonamide (73)1-Chloro-2-(propan-2-ylsulfanyl)benzene

To a solution of sodium methoxide (5.6 g, 103.7 mmol) in MeOH (100 mL)was added 2-chlorobenzene-1-thiol (10.0 g, 69.1 mmol) in MeOH (50 mL).The reaction was cooled to 0° C. and a solution of 2-iodopropane (7.26mL, 72.6 mmol) in MeOH (50 mL) was added dropwise. The reaction wasstirred for 18 hours at a temperature of about 25° C. where upon LC-MSshowed starting material still present. An additional portion of2-iodopropane (3 mL, 30 mmol) and sodium methoxide (3 g, 29 mmol) wasadded and stirring continued for a further 18 hours until completeconsumption of the starting material was observed by LC-MS. The solventwas removed and the reaction quenched by the addition of water (100 mL).The organics were extracted into DCM (3×200 mL), combined, dried oversodium sulfate, filtered and concentrated under reduced pressure toprovide the desired compound as a clear oil (12.8 g, 99% yield). ¹H NMR(CDCl₃, 500 MHz) δ ppm 7.39 (2H, d, 7.9 Hz), 7.21 (1H, td, 7.6, 1.4 Hz),7.14 (1H, td, 7.7, 1.6 Hz), 3.50 (1H, hept, 6.7 Hz), 1.34 (6H, d, 6.7Hz).

1-Chloro-2-(propane-2-sulfonyl)benzene

A solution of 1-chloro-2-(propan-2-ylsulfanyl)benzene (12.8 g, 68.3mmol) in DCM (230 mL) was added over 1 hour to a 0-5° C. solution of 10%sulfuric acid (380 mL) with simultaneous addition of potassiumpermanganate solid (36.7 g, 0.23 mol) in portions. The resultingreaction mixture was allowed to warm to a temperature of about 25° C.and stirring was continued for 1 hour after which time, LC-MS showed thereaction to be complete. Sodium bisulfite (60 g) was added to thereaction mixture slowly until all color had disappeared from thereaction and a clear, colorless solution was observed and the organicphase separated. The aqueous phase was re-extracted into DCM (3×100 mL)and the combined organic portion was dried over sodium sulfate, filteredand concentrated under reduced pressure to provide the desired compoundas a clear, colorless oil (13.7 g, 92% yield). ¹H NMR (CDCl₃, 250 MHz) δppm 8.17-8.06 (1H, m), 7.62-7.52 (2H, m), 7.46 (1H, ddd, 8.7, 5.5, 3.2Hz), 3.80 (1H, hept, 6.9 Hz), 1.32 (6H, dd, 6.9, 0.9 Hz).

1-(Benzylsulfanyl)-2-(propane-2-sulfonyl)benzene

To a solution of 1-chloro-2-(propane-2-sulfonyl)benzene (13.7 g, 62.6mmol) in DMSO (70 mL) was added (benzylsulfanyl)methanimidamide HCl(13.3 g, 65.8 mmol) was added and the reaction mixture was cooled to 10°C. NaOH (6.3 g, 156.6 mmol) was added to the reaction mixture and thereaction was heated to 75° C. for 18 hours. The reaction was quenched bythe addition of water (50 mL) and the resulting aqueous solutionextracted into DCM (4×100 mL). The combined organics were washed withbrine solution (50 mL), dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide the product as a yellowoil which was chromatographed with a silica gel column eluting with50-100% DCM acetate:heptanes gradient to provide the desired compound asa yellow oil (4.7 g, 20% yield). ¹H NMR (CDCl₃, 500 MHz) δ ppm 8.03-7.98(1H, m), 7.50-7.45 (2H, m), 7.36-7.21 (6H, m), 4.23 (2H, s), 3.82 (1H,dt, 13.7, 6.9 Hz), 1.19 (6H, d, 6.9 Hz).

2-(Propane-2-sulfonyl)benzene-1-sulfonyl chloride

Chlorine gas was bubbled through a solution of1-(benzylsulfanyl)-2-(propane-2-sulfonyl)benzene (4.1 g, 13.4 mmol) inacetic acid (140 mL) and water (12 mL) maintaining an internaltemperature of <10° C. for 1 hour. Upon complete addition of thechlorine gas the sulfonyl chloride was extracted into DCM (100 mL) andwas washed with water (100 mL) and 2.5% w:v NaOH solution (50 mL). Theorganic portion was dried over sodium sulfate, filtered and concentratedunder reduced pressure. The resulting solid was triturated with heptanesto provide the desired compound as a white solid (2.9 g, 77% yield). ¹HNMR (CDCl₃, 500 MHz) δ ppm 8.42 (1H, dd, 7.8, 1.4 Hz), 8.34 (1H, dd,7.6, 1.6 Hz), 7.93 (2H, dtd, 20.1, 7.5, 1.4 Hz), 4.05 (1H, hept, 6.8Hz), 1.35 (6H, d, 6.9 Hz).

N-Hydroxy-2-(propane-2-sulfonyl)benzene-1-sulfonamide

N-Hydroxy-2-(propane-2-sulfonyl)benzene-1-sulfonamide was prepared from2-(propane-2-sulfonyl)benzene-1-sulfonyl chloride (1.0 g, 3.5 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was triturated with heptanes to provide thedesired compound as a white solid (0.84 g, 85% yield). ¹H NMR (DMSO, 500MHz) δ ppm 10.11 (1H, d, 3.5 Hz), 8.93 (1H, d, 3.5 Hz), 8.26-8.22 (1H,m), 8.22-8.17 (1H, m), 8.06-7.99 (2H, m), 4.09 (1H, hept, 6.9 Hz), 1.22(6H, d, 6.8 Hz).

Example 864-Acetyl-N-hydroxy-3,4-dihydro-2H-1,4-benzoxazine-6-sulfonamide (74)

4-Acetyl-N-hydroxy-3,4-dihydro-2H-1,4-benzoxazine-6-sulfonamide wasprepared from 4-acetyl-3,4-dihydro-2H-1,4-benzoxazine-6-sulfonylchloride (0.72 g, 2.6 mmol) according to the herein-described methodsfor the synthesis of N-hydroxysulfonamides and was triturated withdiethyl ether to provide the desired compound as a white solid (0.70 g,59% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.50 (1H, br. s.), 9.43 (1H,br. s.), 7.47 (1H, d, 8.4 Hz), 7.09 (1H, d, 8.5 Hz), 4.36 (2H, t, 4.3Hz), 3.89 (2H, t, 4.4 Hz), 2.27 (3H, s).

Example 87 Methyl 5-(hydroxysulfamoyl)-1-methyl-1H-pyrrole-2-carboxylate(75)

Methyl 5-(hydroxysulfamoyl)-1-methyl-1H-pyrrole-2-carboxylate wasprepared from methyl5-(chlorosulfonyl)-1-methyl-1H-pyrrole-2-carboxylate (0.46 g, 1.9 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was triturated with diethyl ether to providethe desired compound as a white solid (0.09 g, 19% yield). ¹H NMR (500MHz, DMSO-d₆) δ ppm 9.47 (1H, d, 3.3 Hz), 9.21 (1H, d, 3.5 Hz), 7.70(1H, d, 1.6 Hz), 7.06 (1H, d, 1.9 Hz), 3.91 (3H, s), 3.78 (3H, s).

Example 88 N-[5-(Hydroxysulfamoyl)-1,3-thiazol-2-yl]acetamide (76)

N-[5-(Hydroxysulfamoyl)-1,3-thiazol-2-yl]acetamide was prepared from2-(acetylamino)-1,3-thiazole-5-sulfonyl chloride (0.28 g, 1.3 mmol)according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was triturated with diethyl ether to providethe desired compound as a white solid (0.12 g, 42% yield). ¹H NMR (500MHz, DMSO-d₆) δ ppm 9.80 (1H, d, 3.2 Hz), 9.65 (1H, d, 3.3 Hz), 7.94(1H, s), 2.20 (3H, s).

Example 89N-Hydroxy-2,5-dimethyl-4-(morpholine-4-carbonyl)furan-3-sulfonamide (77)4-(2,5-Dimethylfuran-3-carbonyl)morpholine

To a solution of diisopropylethylamine (3.8 mL, 21.5 mmol) andmorpholine (1.79 g, 20.5 mmol) in DCM (30 mL) cooled to 0° C. was added2,5 dimethyl-furan-3-carbonyl chloride (3.1 g, 19.6 mmol) and theresulting solution was warmed to a temperature of about 25° C. for 6hours. The reaction was quenched by the addition of 1N HCl (20 mL) andthe organic portion was extracted into DCM (50 mL), dried over sodiumsulfate, filtered and concentrated under reduced pressure to provide thedesired compound as a brown oil (4.41 g, quantitative yield). ¹H NMR(500 MHz, DMSO-d₆) δ ppm 6.09 (1H, s), 3.40-3.63 (8H, m), 2.25 (3H, s),2.21 (3H, s).

2,5-Dimethyl-4-(morpholine-4-carbonyl)furan-3-sulfonyl chloride

4-(2,5-Dimethylfuran-3-carbonyl)morpholine (2.0 g, 9.6 mmol) was addedto chlorosulfonic acid (6.4 mL, 95 mmol) and the reaction heated to 90°C. for 1 hour after which time LC-MS showed complete consumption of thestarting material. The brown solution was poured onto ice and theorganic portion extracted into DCM (2×50 mL), dried over sodium sulfate,filtered and concentrated under reduced pressure to provide the desiredcompound as a brown solid which was used directly in the synthesis ofthe corresponding N-hydroxysulfonamide (2.29 g, 78% yield). ¹H NMR (500MHz, DMSO-d₆) δ ppm 3.03-3.85 (8H, m), 2.31 (3H, s), 2.07 (3H, s).

N-Hydroxy-2,5-dimethyl-4-(morpholine-4-carbonyl)furan-3-sulfonamide

N-Hydroxy-2,5-dimethyl-4-(morpholine-4-carbonyl)furan-3-sulfonamide wasprepared from 2,5-dimethyl-4-(morpholine-4-carbonyl)furan-3-sulfonylchloride (2.3 g, 7.4 mmol) according to the herein-described methods forthe synthesis of N-hydroxysulfonamides and was triturated with DCM toprovide the desired compound as an off white solid (1.3 g, 56% yield).¹H NMR (500 MHz, DMSO-d₆) δ ppm 9.71 (1H, d, 3.5 Hz), 8.64 (1H, d, 3.6Hz), 3.62-3.78 (2H, m), 3.42-3.62 (4H, m), 3.36-3.42 (2H, m), 2.47 (3H,s), 2.22 (3H, s).

Example 90 Ethyl 5-(hydroxysulfamoyl)furan-3-carboxylate (78)

Ethyl 5-(hydroxysulfamoypfuran-3-carboxylate was prepared from ethyl5-(chlorosulfonyl)furan-3-carboxylate (0.3 g, 1.4 mmol) according to theherein-described methods for the synthesis of N-hydroxysulfonamides andwas triturated with heptane to provide the desired compound as an offwhite solid (0.2 g, 60% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 10.14(1H, br. s.), 9.88 (111, s), 8.76 (1H, d, 0.8 Hz), 7.38 (1H, d, 0.8 Hz),4.28 (2H, q, 7.1 Hz), 1.21-1.35 (3H, t, 7.1 Hz).

Example 91 5-Chlorothiophene-2-sulfonamido oxane-4-carboxylate (79)[(tert-Butoxy)carbonyl]amino oxane-4-carboxylate

To a solution of tetrahydro-2H-pyran-4-carboxylic acid (5.0 g, 38.42mmol) in DCM (200 mL) was added EDCI (5.96 g, 38.42 mmol). The reactionwas stirred at a temperature of about 25° C. for 10 minutes and BOChydroxylamine (5.12 g, 38.42 mmol) was added and stirring was continuedfor 18 hours. The reaction mixture was diluted with DCM (50 mL) andwashed with water (2×20 mL) and brine (1×20 mL), dried over magnesiumsulfate, filtered and concentrated to give [(tert-butoxy)carbonyl]aminooxane-4-carboxylate as a light orange oil (6.93 g, 74% yield). ¹H NMR(250 MHz, chloroform-d) δ ppm 8.00 (1H, br. s.), 3.98 (2H, td, 3.7, 11.7Hz), 3.60-3.32 (2H, m), 2.86-2.64 (1H, m), 1.79 (4H, s), 1.48 (9H, s).

N-[(tert-Butoxy)carbonyl]5-chlorothiophene-2-sulfonamidooxane-4-carboxylate

To a solution of [(tert-butoxy)carbonyl]amino oxane-4-carboxylate (2 g,8.15 mmol) in DCM (100 mL) was added 5-chlorothiophene-2-sulfonylchloride (1.09 mL, 8.15 mmol) and triethylamine (1.7 mL, 12.23 mmol),followed by the addition of DMAP (149 mg, 1.22 mmol). The reactionmixture was stirred at a temperature of about 25° C. for 1 hour and thenwater was added (10 mL). The mixture was shaken, the 2 layers wereseparated and the organic layer was washed with aqueous 0.1M HCl (1×10mL), water (1×10 mL) and brine (1×10 mL), dried over magnesium sulfate,filtered and concentrated under reduced pressure to give an oil. Theproduct was chromatographed with a silica gel column eluting withheptane:EtOAc 30%-40% to giveN-[(tert-butoxy)carbonyl]5-chlorothiophene-2-sulfonamidooxane-4-carboxylate (0.92 g, 27% yield). ¹H NMR (500 MHz, chloroform-d)δ ppm 7.65 (1H, d, 4.3 Hz), 7.00 (1H, d, 4.1 Hz), 4.01 (2H, td, 3.6,11.7 Hz), 3.55-3.46 (2H, m), 2.84 (1H, tt, 5.1, 9.8 Hz), 2.00-1.87 (4H,m), 1.49 (9H, s).

5-Chlorothiophene-2-sulfonamido oxane-4-carboxylate

To a solution ofN-[(tert-butoxy)carbonyl]5-chlorothiophene-2-sulfonamidooxane-4-carboxylate (0.86 g, 2.0 mmol) in DCM (8 mL) was addedtrifluoroacetic acid (2.24 mL, 30.3 mmol) and the reaction mixture wasstirred at a temperature of about 25° C. for 1 hour. The solvents wereevaporated to give a yellow oil which was chromatographed with a silicagel column eluting with heptanes:EtOAc 20%-50% to give5-chlorothiophene-2-sulfonamido oxane-4-carboxylate as a white solid(0.53 g, 80% yield). ¹H NMR (500 MHz, DMSO-d₆) δ ppm 11.52 (1H, br. s.),7.68 (1H, d, 4.1 Hz), 7.39 (1H, d, 4.1 Hz), 3.80 (2H, td, 3.5, 11.3 Hz),3.41-3.30 (2H, m), 2.78 (1H, tt, 4.1, 11.1 Hz), 1.73 (2H, dd, 2.1, 12.8Hz), 1.62-1.49 (2H, m).

Example 92 N-Hydroxy-2-(oxan-4-ylmethanesulfonyl)benzene-1-sulfonamide(80) 4-[(2-Fluorobenzenesulfonyl)methyl]oxane

To a solution of 4-(iodomethyl)oxane (1.0 g, 4.4 mmol) and2-fluorobenzene-1-thiol (0.57 g, 4.4 mmol) in DMF (10 mL) was addedpotassium carbonate (0.79 g, 5.7 mmol) and the reaction mixture wasstirred at a temperature of about 25° C. for 18 hours. The reaction wasquenched by the addition of water (20 mL) and the organic portionextracted into DCM (50 mL). The organics were washed with water (10 mL)before being dried over sodium sulfate, filtered and concentrated underreduced pressure. The product was chromatographed with a silica gelcolumn eluting with 100-70% heptanes:ethyl acetate to provide thedesired compound as a clear, colorless oil (0.9 g, 92% yield). ¹H NMR(500 MHz, chloroform-d) δ ppm 7.37 (1H, td, 7.6, 1.7 Hz), 7.18-7.25 (1H,m), 6.99-7.17 (2H, m), 3.85-4.04 (2H, m), 3.35 (2H, td, 11.8, 2.0 Hz),2.84 (2H, d, 6.9 Hz), 1.77-1.87 (2H, m), 1.65-1.77 (1H, m), 1.36 (2H,qd, 12.3, 4.4 Hz).

4-{[2-(Benzylsulfanyl)benzenesulfonyl]methyl}oxane

To a solution of 4-[(2-fluorobenzenesulfonyl)methyl]oxane (1.0 g, 3.9mmol) in DMSO (20 mL) was added benzyl carbamimidothioate hydrochloride(0.84 g, 4.2 mmol) and the mixture was cooled during the addition ofNaOH (0.4 g, 9.8 mmol) so the internal temperature was kept below 15°C.-20° C. The reaction mixture was heated at 75° C. for 2 hours afterwhich time LC-MS shows complete consumption of the starting material.The reaction was allowed to cool to a temperature of about 25° C. andquenched by the addition of 1N HCl solution (5 mL). The formed emulsionwas extracted with ethyl acetate (2×50 mL) and the resulting organiclayer was dried over sodium sulfate, filtered and concentrated underreduced pressure. The oil was chromatographed with a silica gel columneluting with 20-40% heptanes:ethyl acetate to provide the desiredcompound as a yellow oil (1.2 g, 87% yield). ¹H NMR (250 MHz, DMSO-d₆) δppm 7.78-7.95 (2H, m), 7.67 (1H, td, 7.7, 1.5 Hz), 7.14-7.49 (6H, m),4.40 (2H, s), 3.71 (2H, dt, 9.7, 1.9 Hz), 3.30 (2H, d, 6.4 Hz), 3.17(2H, td, 11.6, 2.1 Hz), 1.79-1.97 (1H, m), 1.48 (2H, dd, 13.0, 1.9 Hz),1.06-1.30 (2H, m).

2-(Oxan-4-ylmethanesulfonyl)benzene-1-sulfonyl chloride

Chlorine gas was bubbled through a solution of4-{[2-(benzylsulfanyl)benzenesulfonyl]methyl}oxane (1 g, 2.8 mmol) inacetic acid (35 mL) and water (3 mL) maintaining an internal temperatureof <10° C. for 1 hour. Upon complete addition of the chlorine gas thesulfonyl chloride was extracted into DCM (150 mL) and was washed withwater (150 mL) and 2.5% w:v NaOH solution (50 mL). The organic portionwas dried over sodium sulfate, filtered and concentrated under reducedpressure and chromatographed with a silica gel column eluting with 80%ethyl acetate:heptane to provide the desired compound as an oil whichwas used directly in the synthesis of the correspondingN-hydroxysulfonamide (0.9 g, 96% yield). ¹H NMR (500 MHz, chloroform-d)δ ppm 8.40 (2H, ddd, 7.6, 5.9, 1.4 Hz), 7.88-8.05 (2H, m), 3.87-4.03(2H, m), 3.38-3.51 (3H, m), 2.99 (1H, br. s.), 2.41-2.64 (1H, m),1.80-1.91 (2H, m), 1.43-1.63 (2H, m).

N-Hydroxy-2-(oxan-4-ylmethanesulfonyl)benzene-1-sulfonamide

N-Hydroxy-2-(oxan-4-ylmethanesulfonyl)benzene-1-sulfonamide was preparedfrom 2-(oxan-4-ylmethanesulfonyl)benzene-1-sulfonyl chloride (0.72 g,2.1 mmol) according to the herein-described methods for the synthesis ofN-hydroxysulfonamides and was chromatographed with a silica gel columneluting with heptanes:ethyl acetate (1:1 v:v) to provide the desiredcompound as a white solid (0.37 g, 52% yield). ¹H NMR (500 MHz, DMSO-d₆)δ ppm 10.11 (1H, d, 3.5 Hz), 8.98 (1H, d, 3.5 Hz), 8.23-8.28 (1H, m),8.17-8.22 (1H, m), 7.99-8.04 (2H, m), 3.74-3.81 (2H, m), 3.62 (2H, d,6.5 Hz), 3.29 (2H, td, 11.6, 2.0 Hz), 2.11-2.23 (1H, m), 1.66 (2H, dd,13.1, 1.9 Hz), 1.28-1.40 (2H, m).

Example 93 N-Hydroxy-3-methyl-1-benzofuran-2-sulfonamide (81) Ethyl2-(2-acetylphenoxyl)acetate

To a solution of 1-(2-hydroxyphenyl)ethan-1-one (7.5 g, 0.06 mol) indimethyl formamide (75 mL) was added potassium carbonate (22.8 g, 0.17mol) at a temperature of about 25° C. The reaction mixture was stirredfor 10 minutes before the addition of ethyl bromoacetate (9.2 mL, 0.08mol) and stirring was continued for a further 5 hours at a temperatureof about 25° C. After completion of reaction, observed by TLC, thereaction was diluted with ethyl acetate (150 mL) and water (150 mL), theorganic portion was separated, and the aqueous portion was furtherextracted with ethyl acetate (2×150 mL). The combined organic layerswere washed with water (2×150 mL), dried over sodium sulfate, filteredand concentrated under reduced pressure to provide the O-alkylatedproduct as an colorless oil. The product was chromatographed with asilica gel column eluting with 5-8% ethyl acetate:hexane to give ethyl2-(2-acetylphenoxyl)acetate as an off white solid (10.5 g, 86% yield).¹H NMR (400 MHz, CDCl₃) δ ppm 7.78-7.74 (1H, m), 7.47-7.41 (1H, m),7.08-7.02 (1H, m), 6.85-6.80 (1H, m), 4.72 (2H, s), 4.28 (2H, q, 7.1Hz), 2.72 (3H, s), 1.30 (3H, t, 7.1 Hz).

2-(2-Acetylphenoxy)acetic acid

To a solution of ethyl 2-(2-acetylphenoxy) acetate (8 g, 0.04 mol) inethanol:water (80 mL:8 mL) was added lithium hydroxide hydrate (1:1:1)(4.5 g, 0.11 mol) at 0° C. The reaction mixture was stirred at atemperature of about 25° C. for 18 hours and after completion ofreaction (observed by TLC), the reaction mixture was concentrated underreduced pressure. The product was taken into water (350 mL) andextracted with diethyl ether (2×150 mL). The aqueous extract was thenacidified using 1N HCl (pH of about 2-3) at 0° C. and extracted intodichloromethane (4×300 mL). The combined organic layers were washed withwater (150 mL), dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the acid product as an off whitesolid. Trituration with pentane provided the product compound as an offwhite solid (6.7 g, 95.8% yield). ¹H NMR (400 MHz, DMSO) 8 ppm 13.16(1H, s), 7.60-7.55 (1H, m), 7.54-7.49 (1H, m), 7.12-7.07 (1H, m),7.07-7.02 (1H, m), 4.85 (2H, s), 2.62 (3H, s).

3-Methyl-1-benzofuran

To a solution of 2-(2-acetylphenoxyl)acetic acid (8 g, 0.041 mol) inacetic anhydride (48 mL) was added sodium acetate (20.3 g, 0.25 mol) ata temperature of about 25° C. The reaction mixture was stirred at reflux(140° C.) for 18 hours. Upon reaction completion (checked by TLC), thereaction mixture was poured onto ice-cold water (400 mL) and extractedinto ethyl acetate (3×400 mL). The combined organic layer was washedwith water (400 mL), dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide cyclized product as a redoil which was chromatographed with a silica gel column eluting withhexane to provide the cyclized compound as a colorless liquid (2.6 g,48% yield). ¹H NMR (400 MHz, CDCl₃) δ ppm 7.55-7.51 (1H, m), 7.48-7.44(1H, m), 7.42-7.39 (1H, m), 7.32-7.27 (1H, m), 7.27-7.22 (1H, m), 2.26(3H, d, 1.3 Hz).

3-Methyl-1-benzofuran-2-sulfonyl chloride

To a solution of 3-methyl-1-benzofuran (2.6 g, 17.7 mmol) in diethylether (50 mL) cooled to −78° C. was added n-BuLi (8.7 mL of a 2.5Msolution in hexanes, 21.64 mmol) dropwise. The reaction was stirred for1 hour before SO₂ gas was bubbled through the reaction and stirringcontinued at −50° C. for an additional 1 hour. The reaction was allowedto warm to −20° C. and NCS (3.42 g, 25.58 mmol) was added portion wiseand stirring was continued for 18 hours at a temperature of about 25° C.After substantially complete consumption of the starting material wasobserved by TLC, water (40 mL) was added and the organic portion wasextracted into ethyl acetate (3×20 mL), dried over sodium sulfate,filtered and concentrated under reduced pressure. The product waschromatographed with a silica gel column eluting with 0.5% ethyl acetatein hexane to provide the desired compound as a yellow solid (2.5 g, 55%yield). ¹H NMR (300 MHz, CDCl₃) δ ppm 7.72 (1H, dd, 7.9, 0.9 Hz),7.64-7.58 (2H, m), 7.43 (1H, dd, 8.1, 4.2 Hz), 2.65 (3H, s).

N-Hydroxy-3-methyl-1-benzofuran-2-sulfonamide

N-Hydroxy-3-methyl-1-benzofuran-2-sulfonamide was prepared from3-methyl-1-benzofuran-2-sulfonyl chloride (1.5 g, 6.5 mmol) according tothe herein-described methods for the synthesis of N-hydroxysulfonamidesand was triturated with 5% DCM:pentane to provide the desired compoundas a white solid (0.74 g, 50% yield). ¹H NMR (400 MHz, DMSO) 6 ppm 10.11(1H, d, 3.0 Hz), 9.79 (1H, d, 3.0 Hz), 7.81 (1H, ddd, 7.9, 1.1, 0.7 Hz),7.70-7.66 (1H, m), 7.55 (1H, ddd, 8.4, 7.2, 1.3 Hz), 7.41 (1H, td, 7.6,0.9 Hz), 2.50 (3H, s).

Example 94 N-Hydroxy-5-(piperidine-1-carbonyl)furan-2-sulfonamide (82)5-(Piperidine-1-carbonyl)furan-2-sulfonyl chloride

Sulfur trioxide pyridine complex (2.66 g, 16.74 mmol) and 1,2dichloroethane (20 mL) were heated with (furan-2-carbonyl) piperidine (2g, 11.16 mmol) in a sealed tube at 140° C. for 22 hours, after whichtime the reaction mixture was allowed to cool to a temperature of about25° C. and the mixture concentrated under reduced pressure to provide aslurry. The residue was treated with a solution of sodium carbonate (1.7g, 16.74 mmol) in water (20 mL) and the resulting mixture was evaporatedto dryness. The solid was stirred with dichloromethane (20 mL) beforerefluxing in ethanol (10 mL) for 30 min and the filtrate wasconcentrated under reduced pressure to provide 1.2 g of the sodium salt.The sodium salt was dissolved in methanol (10 mL) and the resultingsolution was treated with charcoal and filtered through CELITE. Thefiltrate was concentrated under reduced pressure to provide5-(piperidine-1-carbonyl)furan-2-sulfonic acid as the sodium salt (950mg). The sodium salt was mixed with dichloromethane (10 mL) at 0° C. andslowly added to phosphorous oxychloride (2 mL). Phosphorus pentachloride(2.32 g, 16.74 mmol) was then added portion wise to the reaction mixtureat 0° C. and the reaction mixture was allowed to warm to a temperatureof about 25° C. and stirred for a further 2 hours at that temperature.The reaction mixture was diluted with dichloromethane (30 mL) and water(20 mL), and the organic portion was separated and dried over sodiumsulfate, filtered and concentrated under reduced pressure to provide5-(piperidine-1-carbonyl)furan-2-sulfonyl chloride (0.6 g, 19% yield).

N-Hydroxy-5-(piperidine-1-carbonyl)furan-2-sulfonamide

To a solution of aqueous hydroxylamine (0.3 mL of a 50% aqueoussolution, 4.95 mmol) in tetrahydrofuran (7 mL) and water (3 mL) cooledto −5° C. was slowly added a solution of5-(piperidine-1-carbonyl)furan-2-sulfonyl chloride (550 mg, 1.98 mmol)in THF (3 mL), maintaining a reaction temperature of less than 10° C.The reaction was maintained at this temperature until substantiallycomplete consumption of the sulfonyl chloride was observed by TLC (about30 min), after which time the reaction was diluted with dichloromethane(20 mL) and the organic portion was separated, washed with water (2×10mL), dried over sodium sulfate, filtered and concentrated under reducedpressure to provide theN-hydroxy-5-(piperidine-1-carbonyl)furan-2-sulfonamide as an yellowsolid. Trituration was carried out using DCM:pentane (1:1 v:v) followedby dichloromethane (2×1 mL) to provide the title compound as an offwhite solid (0.3 g, 55% yield). ¹H NMR (400 MHz, DMSO) 6 ppm 10.13 (s,¹H), 9.84 (s, 1H), 7.31 (d, 1H), 7.09 (d, 1H), 3.58 (s, 4H), 1.74-1.45(m, 6H)

Example 95 N-Hydroxy-5-methanesulfonylthiophene-2-sulfonamide (83)5-Methanesulfonylthiophene-2-sulfonyl chloride

2-Methanesulfonylthiophene (5 g, 30.82 mmol) was added to chlorosulfonicacid (14.37 mL, 215.74 mmol) and the resulting solution was heated to90° C. for 1 h after which time the solution was cooled to a temperatureof about 25° C. before being poured onto ice (250 mL). The resultingsuspension was extracted into dichloromethane (3×100 mL) and thecombined organic portion was dried over sodium sulfate, filtered andconcentrated under reduced pressure to provide the desired compound as afawn solid which existed as a mixture with the corresponding 1,4 isomerand was used as such directly in the synthesis the correspondingN-hydroxysulfonamide (4.6 g, 39% yield as a 1:1 mixture with the 2,4isomer). ¹H NMR (500 MHz, DMSO-d₆) δ 7.59 (d, J=3.8 Hz, 1H), 7.20 (d,J=3.8 Hz, 1H), 3.33 (s, 3H).

N-Hydroxy-5-methanesulfonylthiophene-2-sulfonamide

To a solution of aqueous hydroxylamine (158 mL of a 50% solution, 23.97mmol) in tetrahydrofuran (15 mL) and water (2.5 mL) cooled to −5° C. wasslowly a 1:1 mixture of 5-methanesulfonylthiophene-2-sulfonyl chlorideand 5-methanesulfonylthiophene-3-sulfonyl chloride (2.5 g, 9.58 mmol)maintaining a reaction temperature of less than 10° C. The reaction wasmaintained at this temperature until complete consumption of thesulfonyl chloride was observed by LC-MS (about 5 min), after which timethe reaction was diluted with dichloromethane (20 mL) and the organicportion was separated, washed with water (2×5 mL), dried over sodiumsulfate, filtered and concentrated under reduced pressure to provide theN-hydroxysulfonamide as a 1:1 mixture with the corresponding 2,4 isomeras a by-product. The compound was then chromatographed by acidic HPLCwhich fully separated the 2 isomers (0.58 g, 46% yield). ¹H NMR (500MHz, DMSO-d₆) of title compound: δ 10.09 (s, 2H), 7.91 (d, J=4.0 Hz,1H), 7.75 (d, J=4.0 Hz, 1H), 3.48 (s, 3H). ¹H NMR (500 MHz, DMSO-d₆) of2,4 isomer: ¹H NMR (500 MHz, DMSO-d₆) δ 9.84 (s, 1H), 9.77 (s, 1H), 8.65(d, J=1.6 Hz, 1H), 7.99 (d, J=1.6 Hz, 1H), 3.46 (s, 4H).

Example 96 Preparation of N-Hydroxy-5-methylthiophene-2-sulfonamide (84)5-Methylthiophene-2-sulfonyl chloride

5-Methylthiophene-2-sulfonyl chloride was synthesized according to themethods disclosed in Sone et al., Bull. Chem. Soc. Japan 58:1063-1064(1985). Freshly distilled sulfuryl chloride (74.9 mL, 0.93 mol) wasadded drop wise with stirring to ice cold DMF (71.5 mL, 0.93 mol)maintaining a temperature below 25° C. The hygroscopic solid complexwhich formed after 10 minutes was held at the same temperature for anadditional 30 minutes. 2-methyl thiophene (70 g, 0.71 mol) was added tothe complex and the mixture was heated at 98° C. for 1 hour. The viscousbrown mixture was cooled, poured into ice-water and extracted intodiethyl ether (2×1 L). The organic layer was washed successively withwater (500 mL), 5% NaHCO₃ solution (200 mL) and water (500 mL) beforebeing dried over sodium sulfate, filtered and concentrated under reducedpressure to provide the sulfonyl chloride as a dark brown liquid. Thesulfonyl chloride was chromatographed by CC eluting with 0-30%EtOAc:heptane (110 g, 78% yield). ¹H NMR (400 MHz, CDCl₃) δ ppm 7.69(1H, d, J=3.9 Hz), 6.88-6.83 (1H, m), 2.60 (3H, d, J=0.8 Hz).

N-Hydroxy-5-methylthiophene-2-sulfonamide

To a solution of aqueous hydroxylamine (8.4 mL of a 50% aqueoussolution, 50.9 mmol) in THF (60 mL) and water (10 mL) cooled to −5° C.was slowly added 5-methylthiophene-2-sulfonyl chloride (10 g, 50.9 mmol)maintaining a reaction temperature of less than 10° C. The reaction wasmaintained at this temperature until complete consumption of thesulfonyl chloride was observed by LC-MS (about 5 min), after which timethe reaction was diluted with DCM (100 mL) and the organic portion wasseparated and washed with water (2×25 mL). The aqueous extracts werecombined and rewashed with DCM (2×75 mL). All of the organic portionswere combined, dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the N-hydroxysulfonamide as a beigesolid. Trituration with heptanes provided the title compound as a beigesolid (6.1 g, 61.8% yield). LC-MS t_(R)=1.1 min; HRMS: theoretical(C₅H₇NO₃S₂)=191.9789, measured=191.9781; ¹H NMR (500 MHz, DMSO-d₆) δ ppm9.71 (1H, d, J=3.3 Hz), 9.58 (1H, d, J=3.5 Hz), 7.46 (1H, d, J=3.8 Hz),6.95 (1H, dd, J=3.7, 1.0 Hz), 2.53 (3H, s).

Example 97 N-Hydroxy-1-methyl-1H-pyrazole-3-sulfonamide (85)

To a solution of aqueous hydroxylamine (7.32 mL of a 50% solution,110.73 mmol) in tetrahydrofuran (48 mL) and water (8 mL) cooled to −5°C. was slowly added 1-methyl-1H-pyrazole-3-sulfonyl chloride (8 g, 44.29mmol) maintaining a reaction temperature of less than 10° C. Thereaction was maintained at this temperature until substantially completeconsumption of the sulfonyl chloride was observed by TLC (about 5 min),after which time the reaction was diluted with dichloromethane (50 mL)and the organic portion was separated, washed with water (2×10 mL),dried over sodium sulfate, filtered and concentrated under reducedpressure to provide the N-hydroxysulfonamide as an off white solid.Trituration was carried out using heptanes:DCM (1:1, v:v) to provide thetitle compound as an off white solid (4.3 g, 55% yield). LC-MSt_(R)=0.41 min, [M+H]⁺=179. ¹H NMR (250 MHz, DMSO-d₆) δ ppm 9.62 (d,J=3.2 Hz, 1H), 9.51 (d, J=3.2 Hz, 1H), 7.89 (d, J=2.3 Hz, 1H), 6.68 (d,J=2.3 Hz, 1H), 3.93 (s, 3H).

Example 98 Preparation of3-Chloro-4-fluoro-N-hydroxybenzene-1-sulfonamide (87)

To a solution of hydroxylamine (1.3 mL of a 50% aqueous solution; 21.8mmol) in THF (12 mL) and water (2 mL) cooled to 0° C. was added3-chloro-4-fluorobenzene-1-sulfonyl chloride (2 g, 8.7 mmol) portionwiseso as to maintain the temperature below 10° C. The reaction was stirredfor 20 minutes, after which time LC-MS showed complete consumption ofthe sulfonyl chloride. The reaction was diluted with diethyl ether (2×50mL) and the organic portion was separated and washed with 5% citric acidsolution (10 mL) and water (10 mL). The organic portion was dried oversodium sulfate, filtered and concentrated under reduced pressure. Theproduct was triturated with diethyl ether:heptane to provide the titlecompound as a white solid (1.14 g, 58% yield). LC-MS t_(R)=1.54 min;HRMS: theoretical (C₆H₅ClFNO₃S)=223.9584, measured=223.963; ¹H NMR (500MHz, DMSO-d₆) δ ppm 9.79 (1H, d, 3.2 Hz), 9.73 (1H, d, 3.2,Hz), 7.98(1H, dd, 6.87 Hz, 2.29,Hz), 7.85 (1H, m).

Example 99 1-N,3-N-dihydroxybenzene-1,3-disulfonamide (88)

To a solution of aqueous hydroxylamine (2.4 mL of a 50% solution, 36.35mmol) in tetrahydrofuran (12 mL) and water (2 mL) cooled to −0.5° C. wasslowly added benzene-1,3-disulfonyl dichloride (2 g, 7.27 mmol),maintaining a reaction temperature of less than 10° C. The reaction wasmaintained at this temperature until substantially complete consumptionof the sulfonyl chloride was observed by TLC (about 5 min), after whichtime the reaction was diluted with ethyl acetate (25 mL) and the organicportion was separated, washed with water (2×10 mL), and ammoniumchloride (25 mL), dried over sodium sulfate, filtered and concentratedunder reduced pressure to provide the N-hydroxysulfonamide as a whitesolid. Trituration was carried out using heptane to provide the titlecompound as a white solid (0.567 g, 29% yield). Concentration to ⅓volume of the filtrate provided a second batch of theN-hydroxysulfonamide (0.327 g, 17% yield) LC-MS t_(R)=0.87 min; ¹H NMR(500 MHz, DMSO-d₆) δ 9.88 (s, 2H), 9.82 (s, 2H), 8.28 (t, J=1.7 Hz, 1H),8.14 (dd, J=7.9, 1.8 Hz, 2H), 7.91 (t, J=7.9 Hz, 1H).

Example 100 3-Bromo-N-hydroxybenzene-1-sulfonamide (89)

To a solution of hydroxylamine HCl (1.62 g, 23.48 mmol) in water (2.4mL) cooled to 0° C. was added a solution of potassium carbonate (3.24 g,23.48 mmol) in water (3.6 mL) dropwise maintaining an internal reactiontemperature between 5° C. and 15° C. The reaction mixture was stirredfor 15 minutes, whereupon tetrahydrofuran (12 mL) and methanol (3.0 mL)were added. 3-Bromobenzene sulfonyl chloride (3.0 g, 11.74 mmol) wasadded portionwise maintaining a temperature below 15° C. and thereaction mixture was then stirred at a temperature of about 25° C. untilsubstantially complete consumption of the sulfonyl chloride was observedby TLC. The resulting suspension was concentrated under reduced pressureto remove any volatiles and the aqueous suspension was extracted withdiethyl ether (2×50 mL). The organic portion was dried over magnesiumsulfate, filtered and concentrated under reduced pressure to provide theN-hydroxy sulfonamide as a white solid (1.8 g, 61% yield). ¹H NMR (400MHz, DMSO-d₆) δ ppm 9.75 (1H, d, J=8.1 Hz), 9.77 (1H, s), 7.92 (1H, d,J=8.1 Hz), 7.95 (1H, t, J=1.7 Hz), 7.84 (1H, d, J=7.8 Hz), 7.60 (1H, t,J=7.9 Hz); predicted [M−H]⁻=249.9174; observed [M−H]⁻=249.9163.

Example 101 Preparation ofN-Hydroxy-3-(trifluoromethoxy)benzene-1-sulfonamide (92)

To a solution of hydroxylamine (6.4 mL of a 50% aqueous solution; 95.9mmol) in THF (60 mL) and water (10 mL) cooled to 0° C. was added3-(trifluoromethoxy)benzene-1-sulfonyl chloride (10 g, 38.4 mmol)portionwise so as to maintain the temperature below 10° C. The reactionwas stirred for 20 minutes, after which time LC-MS showed completeconsumption of the sulfonyl chloride. The reaction was diluted with DCM(2×50 mL) and the organic portion was separated and washed with ammoniumchloride solution (10 mL) and water (10 mL). The organic portion wasdried over sodium sulfate, filtered and concentrated under reducedpressure. The product was triturated with heptane to provide the titlecompound as a white solid (6.77 g, 66.6% yield). LC-MS t_(R)=1.67 min;HRMS: theoretical (C₇H₆F₃NO₄S)=255.9891, measured=255.9903; ¹H NMR (250MHz, DMSO-d₆) δ ppm 9.82 (2H, s), 7.89 (1H, dt, J=7.3, 1.7 Hz),7.84-7.70 (3H, m).

Example 102 N-Hydroxy-4-methanesulfonylbenzene-1-sulfonamide (93)

To a solution of aqueous hydroxylamine (6.48 mL of a 50% solution, 98.15mmol) in tetrahydrofuran (60 mL) and water (10 mL) cooled to −5° C. wasslowly added 4-methanesulfonylbenzene-1-sulfonyl chloride (10 g, 39.26mmol) as a suspension in tetrahydrofuran (20 mL) maintaining a reactiontemperature of less than 10° C. The reaction was maintained at thistemperature until complete consumption of the sulfonyl chloride wasobserved by LC-MS (about 10 min), after which time the reaction wasdiluted with dichloromethane (150 mL) and the organic portion wasseparated, washed with water (2×25 mL), dried over sodium sulfate,filtered and concentrated under reduced pressure to provide theN-hydroxysulfonamide as an off white solid. Trituration was carried outusing heptanes:DCM (9:1 v:v) to provide the title compound as an offwhite solid (5.46 g, 55.4% yield). LC-MS t_(R)=0.89 min, [M−H]⁻=250; ¹HNMR (500 MHz, DMSO-d₆) δ ppm 9.89 (1H, d, J=2.4 Hz), 9.85 (1H, d, J=2.4Hz), 8.19 (2H, d, J=8.4 Hz), 8.08 (2H, d, J=8.4 Hz), 3.32 (3H, s).

It will be apparent to those in the art that specific embodiments of thedisclosed subject matter may be directed to one or more of the above-and below-indicated embodiments

While the invention has been disclosed in some detail by way ofillustration and example for purposes of clarity of understanding, it isapparent to those in the art that various changes may be made andequivalents may be substituted without departing from the true spiritand scope of the invention. Therefore, the description and examplesshould not be construed as limiting the scope of the invention.

All references, publications, patents, and patent applications disclosedherein are hereby incorporated by reference in their entirety.

1. A method of treating heart failure, comprising administering to ahuman patient a nitroxyl donor composition, said composition comprisinga N-hydroxysulfonamide type nitroxyl donor that has a half-life ofgreater than 10 minutes when measured in human plasma at a pH of 7.4 bythe procedure described in Example 2 and a cyclodextrin.
 2. (canceled)3. The method of claim 1, wherein the N-hydroxysulfonamide type nitroxyldonor has a half-life of from about 25 minutes to about 75 minutes whenmeasured in human plasma at a pH of 7.4 under conditions specified inExample
 2. 4. The method of claim 1, wherein the N-hydroxysulfonamidetype nitroxyl donor has a half-life of less than 95 minutes whenmeasured in human plasma at a pH of 7.4 under conditions specified inExample
 2. 5. The method of claim 1, wherein the cyclodextrin is asulfo-n-butyl ether derivative of β-cyclodextrin having six or sevensulfo-n-butyl ether groups per cyclodextrin molecule.
 6. The method ofclaim 1, wherein the cyclodextrin is CAPTISOL®.
 7. The method of claim1, wherein the molar ratio between the N-hydroxysulfonamide typenitroxyl donor and the cyclodextrin present in the composition is fromabout 0.02:1 to about 2:1.
 8. (canceled)
 9. The method of claim 1,wherein the molar ratio between the N-hydroxysulfonamide type nitroxyldonor and the cyclodextrin present in the composition is from about0.5:1 to about 1:1.
 10. The method of claim 1, wherein the compositionis suitable for parenteral administration.
 11. The method of claim 10,wherein the composition is suitable for intravenous administration. 12.The method of claim 1, wherein the composition is formulated at a pH offrom about 4 to about
 6. 13. (canceled)
 14. The method of claim 1,wherein the composition is formulated at a pH of from about 5.5 to about6.
 15. The method of claim 1, wherein the heart failure is acutedecompensated heart failure.
 16. The method of claim 1, wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(1):


17. The method of claim 1, wherein the N-hydroxysulfonamide typenitroxyl donor is a compound of the formula (2):

18-47. (canceled)
 48. A pharmaceutical composition comprising (i) aN-hydroxysulfonamide type nitroxyl donor that has a half-life of greaterthan 10 minutes when measured in human plasma at a pH of 7.4 by theprocedure described in Example 2 and (ii) a cyclodextrin.
 49. Thepharmaceutical composition of claim 48, wherein the N-hydroxysulfonamidetype nitroxyl donor has a half-life of from about 12 minutes to about 85minutes when measured in human plasma at a pH of 7.4 under conditionsspecified in Example
 2. 50. (canceled)
 51. The pharmaceuticalcomposition of claim 48, wherein the N-hydroxysulfonamide type nitroxyldonor has a half-life of less than 95 minutes when measured in humanplasma at a pH of 7.4 under conditions specified in Example
 2. 52. Thepharmaceutical composition of claim 48 wherein the cyclodextrin is asulfo-n-butyl ether derivative of β-cyclodextrin having six or sevensulfo-n-butyl ether groups per cyclodextrin molecule.
 53. Thepharmaceutical composition of claim 48, wherein the cyclodextrin isCAPTISOL®.
 54. The pharmaceutical composition of claim 48, wherein themolar ratio between the N-hydroxysulfonamide type nitroxyl donor and thecyclodextrin present in the composition is from about 0.02:1 to about2:1.
 55. (canceled)
 56. The pharmaceutical composition of claim 48,wherein the molar ratio between the N-hydroxysulfonamide type nitroxyldonor and the cyclodextrin present in the composition is from about0.5:1 to about 1:1.
 57. The pharmaceutical composition of claim 48wherein the N-hydroxysulfonamide type nitroxyl donor is a compound ofthe formula (1):


58. The pharmaceutical composition of claim 48, wherein theN-hydroxysulfonamide type nitroxyl donor is a compound of the formula(2):


59. An admixture comprising a N-hydroxysulfonamide type nitroxyl donorthat has a half-life of greater than 10 minutes when measured in humanplasma at a pH of 7.4 by the procedure described in Example 2 and acyclodextrin, wherein the molar ratio between the N-hydroxysulfonamidetype nitroxyl donor and the cyclodextrin present in the composition isfrom about 0.02:1 to about 2:1. 60.-61. (canceled)
 62. The admixture ofclaim 59 wherein the molar ratio between the N-hydroxysulfonamide typenitroxyl donor and the cyclodextrin present in the composition is fromabout 0.5:1 to about 1:1.
 63. The admixture of claim 59, furthercomprising a buffering agent.
 64. The admixture of claim 63, wherein thebuffering agent is potassium acetate.
 65. The admixture of claim 59,wherein the N-hydroxysulfonamide type nitroxyl donor is a compound ofthe formula (1):


66. The admixture of claim 59, wherein the N-hydroxysulfonamide typenitroxyl donor is a compound of the formula (2):

67.-69. (canceled)
 70. The pharmaceutical composition of claim 48 foruse in the treatment of heart failure.
 71. The pharmaceuticalcomposition of claim 48 for use in the treatment of acute decompensatedheart failure.